i 


•  FROM -THE- 

•SCIENT1FIC-LIBRARY-OF 

•JACQUES -LOEB- 


EVERYMAN'S    CHEMISTRY 


HARPER'S    MODERN     sci E we  s s E R i JE_S 

EVERYMAN'S  CHEMISTRY 

THE    CHEMIST'S    POINT    OF    VIEW 

AND    HIS    RECENT    WORK 

TOLD  FOR  THE  LAYMAN 


BY 

ELLWOOD  HENDRICK 


HARPER  fcf  BROTHERS   PUBLISHERS 
NEW   YORK    AND    LONDON 


HARPER'S  MODERN  SCIENCE  SERIES 


A  new  series  planned  by  Harper  &  Brothers,  an  entirely  modern  scien- 
tific series,  which  will  present  the  latest  and  most  authoritative  pictures  of 
modern  advance  in  scientific  and  sociological  fields.  The  new  world  of 
chemistry,  the  new  discoveries  regarding  life,  and  other  subjects  of  imme- 
diate interest  will  be  presented  for  the  lay  reader  in  this  important  series, 
which  Harper  &  Brothers  have  planned  as  a  distinguished  feature  of 
their  centennial  year. 

THE   OFFENDER 
And  His  Relations  to  Law  and  Society 

BY  BURDETTE  G.  LEWIS 
New  York  City  Commissioner  of  Correction 

"The  latest  word  in  theory  and  practice  of  dealing  with  the  wayward, 
the  delinquents  and  criminals.  .  .  A  great  book  on  a  great  subject  by  a 
great  man." — Journal  of  Education  (Boston). 

"  The  great  merit  of  this  book  is  the  humanity  and  intimacy,  the  famil- 
iarity of  detail  and  truthfulness,  with  which  it  treats  of  four  complicated 
aspects  of  society's  dealing  with  the  wrongdoer:  the  trial  of  suspected 
criminals,  the  questions  of  probation,  parole,  and  the  indeterminate  sen- 
tence, and  the  organization,  procedure,  and  discipline  of  prisons  and  other 
correctional  institutions." — If,  Y.  Nation. 

EVERYMAN'S    CHEMISTRY 
The  Chemist's  Point  of  View  and  His  Present  Work 

BY  ELLWOOD  HENDKICK 
(Other  Volumes  in  Preparation) 

HARPER  &   BROTHERS,   NEW   YORK 
[ESTABLISHED  1817] 


EVERYMAN'S  CHEMISTRY 


Copyright,    1917,   by   Harper  &   Brothers 

Printed  in  the  United  States  of  America 

Published  October,  1917 

K-R 


CONTENTS 

CHAP.  PAGE 

PREFACE vii 

PART  FIRST 
GENERAL  AND  INTRODUCTORY 

I.  CHEMICAL  MISERIES 3 

II.  THE  HEART  OF  THE  THING 16 

III.  PHASES  OF  MATTER 24 

IV.  ELEMENTS  AND  THEIR  COMPOUNDS 38 

V.  CHEMICAL  NAMES  AND  PHRASES 54 

PART  SECOND 
INORGANIC  CHEMISTRY 

VI.  AIR  AND  WATER 59 

VII.  MORE  ABOUT  AIR 77 

VIII.  THE  RED-HEADED  HALOGENS       88 

IX.  SULPHUR,  SULPHURIC  ACID,  AND  SULPHUR  COMPOUNDS  95 

X.  PHOSPHORUS,  ARSENIC,  ANTIMONY,  AND  BISMUTH   .    .  109 

XI.  THE  ALKALI  METALS 117 

XII.  SAND  AND  CLAY 130 

XIII.  LIME  AND  MAGNESIA 148 

XIV.  IRON  AND  STEEL 163 

XV.  MORE  METALS 176 

XVI.  STILL  MORE  METALS 195 

XVII.  SOME  OF  THE  RARER  METALS 203 

XVIII.  CARBON 219 

PART  THIRD 
ORGANIC  CHEMISTRY 

XIX.  PARAFFINS  AND  PETROLEUM  BODIES 235 

XX.  OLEFINS  AND  ACIDS 247 

XXI.  ALCOHOLS  AND  SOME  RELATIVES 258 


778663 


CONTENTS 

CHAP.  PAGE 

XXII.  FATS,  OILS,  AND  THEIR  PRODUCTS 268 

XXIII.  SUGARS,  STARCH  AND  GUMS 282 

XXIV.  CELLULOSE  AND  NITROGEN  COMPOUNDS 303 

XXV.  AROMATIC  COMPOUNDS 315 

XXVI.  COAL-TAR  INTERMEDIATES  AND  FINISHED  PRODUCTS  .  326 

APPENDIX   I — THE   ELEMENTS 347 

APPENDIX  II — BIBLIOGRAPHY 359 

INDEX 363 


PREFACE 

THE  second  decade  of  the  twentieth  century  has 
brought  to  the  average  man  a  general,  if  vague,  realiza- 
tion of  the  tremendous  importance  of  chemistry  and 
its  application  in  actual  life.  I  think  this  has  never 
been  felt  so  acutely  before,  and  yet  it  has  seemed  to  me 
that  the  same  average  man  is  not  very  well  provided 
with  a  work  that  he  could  read  and  understand  easily 
and  at  the  same  time  get  a  chemical  view  of  things. 
To  produce  such  a  book  has  been  my  purpose,  and  if 
I  have  not  made  it  interesting  I  shall  be  to  blame, 
for  I  assure  you  the  subject  is  full  of  interest  and  de- 
light. Of  course  this  is  not  a  complete  treatise  on 
chemistry,  nor  do  I  pretend  that  it  is  a  well-balanced 
book.  Many  important  subjects  are  touched  upon 
but  lightly,  and  others  of  less  general  value  I  have 
not  hesitated  to  ramble  on  about  at  considerable 
length,  so  long  as  they  seemed  interesting.  The 
whole  thing  is,  in  a  way,  a  sporting  proposition  between 
you,  the  reader,  and  me.  If  I  can  hold  your  atten- 
tion until  you  have  read  it  through,  I  shall  have  suc- 
ceeded in  my  undertaking  and  you  will  know  some- 
thing about  the  Ways  of  Stuff  as  the  chemist  has  to 
do  with  them.  You  will  be  out  of  the  inky  darkness. 
You  will  not  think  that  a  barrel  of  coal  -  tar,  for 
instance,  put  into  a  pot  and  boiled  with  a  teacupful 
of  one  thing  and  a  tablespoonful  of  t'other  will 
straightway  resolve  itself  into  dyestuffs,  perfumes, 


PREFACE 

medicines,  and  what  not,  according  to  the  will  of  the 
man  with  the  thermometer.  You  will  not  know  how 
the  chemist  works  so  much  as  you  will  of  the  way  he 
thinks;  and  instead  of  presenting  him  to  you  as  a 
superman  with  potentialities  and  powers  beyond  his 
kind,  I  have  tried  to  make  it  clear  that  his  problems 
are  very  like  those  of  a  business  man.  The  difference 
is  that  the  man  of  affairs  deals  with  others  of  his 
kind  whose  minds  are  hidden  from  him,  trying  to 
induce  them  to  do  his  bidding,  whereas  the  chemist 
deals  with  molecules  and  atoms  and  ions,  none  of 
which  he  can  see,  but  which  also  have  ways  of  their 
own  that  are  often  exceedingly  difficult  to  master. 
My  only  stipulation  is  that  you  shall  not  attempt 
to  read  the  book  backward.  And  yet  I  pray  you  to 
refer  frequently  to  the  table  of  elements  at  the  end. 
It  contains  information  that  you  will  find  useful  as 
you  read  along,  and  I  should  have  put  it  at  the  be- 
ginning had  I  not  feared  that  it  would  frighten  you 
away. 

Chemistry  would  be  the  dullest  study  on  earth  if 
it  only  had  to  do  with  the  proportionate  amounts  of 
oxygen,  nitrogen,  sulphur,  etc.,  that  a  body  contains. 
This  is  merely  the  genealogy  of  things,  and  bears  the 
same  relation  to  them  that  the  names  of  a  man's 
several  grandparents  do  to  him.  The  interest  lies  in 
what  these  things  will  do,  just  as  the  interesting 
quality  of  a  man  lies  in  the  problem  of  what  he  will 
do  under  more  or  less  known  conditions. 

For  those  who  desire  to  read  more  profoundly  I 
have  added  a  select  bibliography  of  standard  works, 
some  of  which  are  easy  to  read  and  some  of  which  are 
written  with  the  understanding  that  the  reader  shall 
have  devoted  several  years  to  the  study  of  the  sub- 
jects treated.  This  appears  in  an  appendix. 


PREFACE 

I  am  indebted  to  more  friends  than  I  can  name  for 
information.  I  have  consulted  with  many  who  are 
actively  engaged  in  special  work  in  chemistry  as  to  the 
status  of  various  industries.  I  spent  some  time  at 
the  Mellon  Institute  of  Industrial  Research,  of  the 
University  of  Pittsburgh,  and,  thanks  to  Dr.  Raymond 
F.  Bacon,  the  Director,  and  many  of  the  Fellows  of 
the  Institute,  I  have  been  able  to  indicate  the  develop- 
ments of  some  subjects  that  would  not  otherwise  have 
been  available  to  me.  Prof.  William  A.  Hamor, 
Assistant  Director  of  the  Institute,  has  set  aside  work 
of  pressing  importance  to  go  over  most  of  the  manu- 
script and  make  suggestions.  The  faults  are  all  mine, 
but  many  of  the  merits  of  the  book,  if  it  should  prove 
to  have  them,  are  the  result  of  his  encyclopedic  knowl- 
edge of  chemical  literature.  In  fact,  the  way  in  which 
my  chemist  friends  offered  their  aid  as  soon  as  I  told 
them  what  I  was  about  to  do  has  made  me  not  only 
very  grateful,  but  has  impressed  upon  me  the  need  of 
just  such  a  book  as  I  have  tried  to  write.  I  offer  my 
hearty  thanks  to  them  all,  and  I  bid  you,  in  all  mod- 
esty, to  enter  with  me  into  what  has  been  called  that 
branch  of  philosophy  and  poetry  which  has  to  do 
with  the  Ways  of  Stuff. 

E.  H. 

139  EAST  40th  STREET,  NEW  YORK, 
June,  1917. 


PART  FIRST 
GENERAL   AND   INTRODUCTORY 


EVERYMAN'S   CHEMISTRY 


CHEMICAL   MISERIES 

The  Troubles  of  Neighbor  Robinson  —  The  Value  of  Chemical  Advice 
and  the  Need  of  Chemical  Control  —  The  Legend  of  the  Dunder- 
head Manufacturing  Company  —  "All  the  Chemistry  We  Need"  — 
Inventors  and  Their  Ways  —  The  Intelligence  Department  of  In- 
dustry 


E£T  us  consider  the  man  on  the  street  —  not  the 
one  leaning  against  a  lamp-post,  but  a  man  of 
circumstance  going  about  his  affairs  —  as  meeting  a 
friend  and  walking  along  with  him.  After  the  usual 
preliminary  greetings,  the  following  conversation 
might  ensue: 

"How  is  Robinson?" 
"I  am  afraid  Robinson  has  pneumonia." 
Then  we  know  what  would  follow.  They  would 
discuss  questions  of  diet,  Robinson's  habits  of  life  and 
his  age,  the  peculiarities  of  the  disease,  the  publications 
of  medical  research  as  recorded  in  the  newspapers, 
and  they  would  talk  as  two  intelligent  men  would 
talk  about  a  frequently  occurring  disease.  They  are 
not  physicians,  but  they  have  a  lay  understanding  of 
the  professional  life  of  the  physician  and  the  manner 
in  which  he  meets  his  problems.  And  they  consider 

3 


EVERYMAN'S   CHEMISTRY 

Robinson's  chances  of  recovery.  A  similar  discussion 
would  follow  the  announcement,  had  it  been  made, 
that  Robinson  had  neuritis,  peritonitis,  appendicitis, 
locomotor  ataxia,  or  any  of  a  score  of  other  diseases 
with  names  having  Latin  and  Greek  entanglements. 

In  other  words,  medicine  has  broken  into  society 
and  it  is  an  interesting  subject  of  the  talk  of  intelligent 
laity  in  their  hours  of  leisure. 

Now  let  us  imagine  that  Robinson  is  whole  in  body, 
but  is  having  business  troubles.  He  is  a  wholesale 
druggist  and  has  been  spending  a  great  deal  of  money 
in  advertising  Robinson's  Liquid  Petrolatum,  which 
is  sold  as  medicine.  Then  the  conversation  might 
take  this  turn : 

"How  is  Robinson?" 

"He  is  in  a  bad  way." 

"Is  he  ill?" 

"No;  it  is  business.  You  know  that  petroleum 
product  he  has  been  advertising?" 

"Yes;  I  thought  it  was  a  gold-mine." 

* '  Not  exactly  that,  although  it  is  an  excellent  thing, 
but  something  has  gone  wrong  and  the  stuff  is  coming 
back  to  him  by  the  car-load.  Smells  like  kerosene 
and  people  don't  like  the  taste  of  it." 

"What  is  the  matter  with  it?" 

"They  say  it  is  olefins."  (In  point  of  fact  it  might 
be  due  to  other  bodies,  but  the  expression  is  conven- 
ient; let's  use  it.) 

"Ole  Fins?    Who's  he?    Is  he  a  Swede?" 

"No;  olefins  are  some  kind  of  unsaturated  hydro- 
carbons and — " 

"Never  mind.  I  don't  know  anything  about 
chemistry." 

"Neither  do  I,  and  I'm  glad  I  don't  have  anything 
to  do  with  it,  You  never  know  where  you  are  with 

4 


CHEMICAL    MISERIES 

chemical  products.  Here's  poor  Robinson,  who  works 
up  a  nice  business  with  that  petroleum  stuff  of  his 
and  then  for  no  reason  at  all  it  goes  back  on  him.'* 

"That's  right.     I'm  sorry  for  Robinson." 

Now  the  first  chapter  of  a  book  is,  in  effect,  an 
advertisement,  designed  to  lure  the  reader  on  into  a 
diligent  perusal  of  what  follows.  Sugar-coat  the  pill 
as  we  may,  that  is  the  problem  of  an  author.  He 
must,  if  he  can,  lure  the  reader  on.  So,  proceeding  as 
though  this  were  printed  in  large,  bold-face  type  and 
adorned  with  illustrations  supposed  to  be  convincing, 
I  ask  you  to  look  upon  the  discussion  of  the  troubles 
of  Robinson,  which  I  have  just  indicated,  as  typical 
of  the  conversation  of  two  intelligent  laymen  who  have 
not  read  this  book.  Permit  me,  then,  to  indicate,  in 
a  few  more  imaginary  conversations  between  the  same 
gentlemen,  types  of  their  intercourse  after  reading. 
Repeat,  if  you  will,  the  same  talk,  beginning  with 
"How  is  Robinson?"  until  the  point  is  reached  where 
olefins  are  supposed  to  constitute  a  Swede.  Now 
observe  the  change: 

"Olefins?" 

"Yes;  unsaturated  hydrocarbons,  you  know." 

"Can't  they  be  separated?" 

"I  believe  they  can.  Trouble  with  Robinson  is, 
I'm  afraid,  he  is  a  little  too  anxious  to  make  money. 
The  United  States  Bureau  of  Mines  has  been  turning 
out  many  papers  on  petroleum,  and  I  understand  that 
at  Columbia  University  and  at  the  Mellon  Institute  in 
Pittsburgh  they  have  been  making  researches  for  years. 
Just  as  likely  as  not  the  information  that  Robinson 
needs  has  been  published  already." 

"Maybe  he  didn't  know  there  were  olefines  in  his 
stuff." 

"Well,  he  ought  to,  and  if  that  is  not  his  trouble  he 

5 


EVERYMAN'S    CHEMISTRY 

ought  to  know  what  is.  What  he  did,  probably,  was 
to  start  with  some  oil  that  was  pretty  clean,  and  then 
when  he  ran  through  a  new  lot  the  agony  began. 
Robinson  is  one  of  those  who  think  that  if  they  have 
a  formula  for  making  something,  any  old  raw  material 
will  do.  He  was  born  about  forty  years  too  late  to 
manufacture  that  way.  Why  didn't  he  take  advice? 
I'm  sorry  for  him,  but  I  hope  this  will  make  him  mend 
his  ways." 

This  criticism  might  not  be  pleasant  for  Robinson, 
but  it  might  be  better  for  him  than  sympathy.  Let  us 
now  make  believe  that  Brown,  another  friend,  is 
having  trouble  because  his  sheds,  which  were  covered 
with  steel  sheeting,  have  rusted  so  that  he  is  using 
up  a  lot  of  his  profits  in  repairs.  Then  the  talk  might 
take  this  turn: 

"Where  did  he  get  his  steel?" 

"He  doesn't  know;  the  contractor  bought  it." 

"Didn't  he  specify  that  he  wanted  copper  alloyed 
with  it?" 

"No;  he  only  specified  the  gauge." 

"Just  think  of  that!  Only  a  little  copper  in  the 
steel,  a  quarter  of  one  per  cent.,  might  have  made  it 
last  years  and  years  instead  of  no  time  at  all.  I'm 
sorry  for  Brown,  but  he  is  getting  just  what  happens 
to  men  who  think  a  practical  man  must  know  every- 
thing. Brown  should  study,  or,  better  still,  seek 
advice." 

This  information  is  not  to  be  found  in  this  book 
alone.  It  is  published  elsewhere  in  much  greater 
detail.  There  is  not  a  single  discovery  here  set  forth 
and  published  for  the  first  time  to  a  supposedly  awe- 
inspired  world.  What  I  am  trying  to  do  is  to  treat  of 
innate  matter,  not  as  though  it  were  dead,  but  rather 
as  having  within  it,  as  it  has,  constant  potentialities 

6 


CHEMICAL   MISERIES 

of  action.  Matter  does  not  act  and  react  according 
to  a  few  fixed  rules;  there  are  rules  by  the  hundred, 
and  we  shall  not  attempt  to  repeat  them.  Then, 
too,  time  and  again,  to  all  intents  and  purposes,  they 
seem  to  be  broken.  There  are  certain  general  princi- 
ples, however,  which  seem  to  hold  good,  just  as  certain 
general  principles  seem  to  hold  good  in  dealing  with 
men.  Some  of  these  I  shall  try  to  indicate  as  we 
proceed.  Every  subject  mentioned  is  a  study  in  itself, 
and  concerning  which,  in  many  cases,  whole  libraries 
have  been  written. 

If  you  want  chemical  advice,  remember  that  nobody 
living  knows  all  there  is  of  chemistry,  but  that  some 
men  are  remarkably  well  informed  on  certain  subjects. 
How  to  find  the  man  you  need  is  an  undeveloped  art, 
but  a  good  thing  to  do  is  to  get  acquainted  with  a 
sound  chemist  and  consult  him  or  talk  with  him  about 
your  business  affairs.  It  is  surprising  into  how  many 
places,  if  he  is  a  sound  man,  he  will  be  able  to  throw 
light.  It  may  interest  you  to  know  that  the  Bureau 
of  Employment  of  the  Chemists'  Club  of  New  York 
maintains  an  excellent  list  of  consultants  and  chem- 
ical engineers  as  well  as  of  chemists  who  seek  employ- 
ment. The  editors  of  the  Journal  of  Industrial  and 
Engineering  Chemistry  of  the  American  Chemical  So- 
ciety and  of  Metallurgical  and  Chemical  Engineering 
are  remarkably  well  posted  as  to  men.  Being  sincerely 
interested  in  the  development  of  American  industrial 
chemistry,  they  are  glad  of  the  opportunity  to  help. 

The  time  is  soon  coming  when  manufacturing  estab- 
lishments will  need  a  chemist  in  consultation  just  as 
much  as  they  need  a  lawyer  now.  If  they  are  negotiat- 
ing with  customers  or  with  other  corporations,  they 
need  a  lawyer  to  draw  their  contracts  and  see  that 
they  do  not  make  mistakes.  Well,  if  they  are  nego- 
2  7 


EVERYMAN'S   CHEMISTRY 

tiating  with  materials,  they  need  a  chemist,  for  chem- 
istry treats  of  the  ways  of  stuff,  and  these  are  full  of 
unexpected  turnings.  Chemical  control  is  needed. 

This  is  bound  to  come,  but  it  hasn't  arrived  yet. 
And  when  it  does  come,  there  are  sure  to  be  comedies 
enacted  in  relation  to  it,  and  very  expensive  comedies 
withal.  Now  the  truth,  as  you  are  likely  to  read 
more  than  once  in  this  book,  is  all  the  facts  arrayed 
in  their  right  relation,  which  is  why  we  do  not  always 
succeed  in  telling  it,  no  matter  how  hard  we  try. 
Teaching  by  parable  is  an  old  and  tried  method,  and, 
in  order  to  bring  out  the  need  of  a  competent  chemist 
in  counsel,  let  us  imagine  a  story.  Before  we  begin, 
however,  please  remember  that  chemistry  is  a  very 
broad  subject,  like  farming.  In  that  profession  one 
man  is  good  at  raising  cattle,  another  breeds  horses, 
another  is  a  great  expert  in  vegetables,  while  others 
are  good  all-round  men  who  do  not  profess  to  know 
everything,  but  have  the  knack  of  getting  needed 
information  and  finding  the  best  authorities.  These 
men  are  likely  to  succeed  as  consultants,  and  of  such 
I  beg  you  to  consider  Doctor  Noyadont,  who  will 
shortly  appear. 

Now  let  us  suppose  a  meeting  of  the  board  of  the 
Dunderhead  Manufacturing  Co.,  and  that,  in  order 
to  conform  to  the  prospective  fashion  of  having  a 
chemist  in  counsel,  the  directors  have  filled  a  vacancy 
by  electing  young  Brown,  who  is  engaged  in  testing 
materials  in  their  cupboard  of  a  laboratory  somewhere 
under  a  stairway.  Then  suppose  the  most  affluent, 
the  most  pompous,  the  vainest  if  not  the  richest  di- 
rector, the  father-in-law  of  the  secretary  of  the  Sand 
&  Stone  Co.,  were  to  offer  the  following  motion: 
"Resolved,  That,  prices  being  equal,  this  corporation 
shall  purchase  its  rock  from  the  Sand  &  Stone  Co." 

8 


CHEMICAL   MISERIES 

The  young  chemist  apologizes  for  speaking,  and  says 
that  Sand  &  Stone  are  agents  for  Blue  Mountain  rock, 
and  that  this  rock  seemed  to  show  traces  of  dubium, 
which  he  fears  might  give  trouble  in  the  works. 

"Whatcha  mean?"  roars  the  affluent  one  to  the 
pale  B.S. 

1  '  Well,  I — er — it  doesn't  seem  to  me  that  it  works 
as  well  as  the  Earth  &  Rock  Co.'s  product  that  I 
believe  comes  from  Green  Mountain.  I  thought  I 
found  traces  of  dubium  there,  and,  you  know,  there 
might  be  a  catalytic  effect — " 

"Cataclysmic  effect,"  exclaims  the  old  heavyweight. 
"Young  man,  is  that  what  you  think  or  what  you 
guess?" 

"Why,  I'm  not  sure,  but  I  think—" 

"That's  what  you  think,  is  it?  Well,  sir,  when  you 
know  something  let's  hear  from  you,  but  we  don't 
care  for  any  of  your  guesses.  The  Sand  &  Stone  Co. 
are  the  largest  dealers  in  this  material  in  the  world, 
and  if  I  tell  them  to  send  us  rock  without  any  of  this 
here  dubium  in  it,  they'll  send  it.  I  call  for  my  mo- 
tion, Mr.  Chairman." 

The  motion  is  put  and  carried. 

In  one  year's  time  the  asset  of  the  corporation's 
name  as  a  trade-mark  becomes  a  liability;  they 
cannot  persuade  people  that  their  product  is  not 
tainted.  Even  after  they  have  seen  the  folly  of  their 
ways  and  given  up  the  use  of  Blue  Mountain  rock 
and  turn  out  a  product  better  than  ever  before,  their 
reputation  is  still  bad. 

"Better  not  buy  of  'em,"  says  one  customer  to  a 
prospective  one.  "They  tried  to  run  off  a  lot  of 
inferior  material  on  me,  but  I  made  'em  take  it  back." 

"One  of  their  drummers  was  in  not  long  ago  and 
he  said  they  had  had  a  fault,  but  had  corrected  it; 

9 


EVERYMAN'S    CHEMISTRY 

they  had  some  sort  of  jubilee  or  other  in  the  rock 
they  make  it  of,  but  he  says  it's  all  right  now." 

"That's  what  they  say.  J'ever  know  a  concern  that 
wasn't  all  right  when  they  wanted  to  make  a  sale?" 

"That's  so.  Better  be  on  the  safe  side,"  says  Mr. 
Prospective  Customer,  and  he  buys  from  the  rival 
company. 

Now  suppose,  instead  of  electing  the  young  chemist 
from  the  works,  a  consulting  chemist  of  standing  is 
selected,  retained  and  added  to  the  board  to  avoid 
mistakes  at  the  start,  which  is  the  Grand  Economy. 
Let  us  imagine  the  same  corporation,  same  chairman 
and  president,  same  pompous  old  party  with  a  son- 
in-law  with  Sand  &  Stone,  same  general  counsel,  and 
the  same  other  members,  except  that  Doctor  Noya- 
dont  of  the  Noyadont  Laboratories  sits  in  the  place 
of  young  Brown,  the  chemist  at  the  works.  Unlike 
Brown,  Doctor  Noyadont  has  not  bought  himself  a 
house  in  the  neighborhood  of  the  factory,  and  has  not 
married  on  the  prospects  of  the  good-will  of  the  very 
board  of  which  he  is  a  member.  Doctor  Noyadont 
likes  his  annual  retainer,  which  may  be  more  than 
Brown's  salary,  but  he  does  not  live  on  it.  Then  let 
us  imagine  the  same  proposal  of  the  affluent  Mr. 
Fatwad  that  the  corporation  procure  its  rock  from 
Sand  &  Stone. 

Doctor  Noyadont  speaks  up:  "Sorry,  Mr.  Fatwad, 
but  I  shall  have  to  oppose  that  motion.  I've  examined 
the  Blue  Mountain  rock  that  they  handle,  and  it  is 
not  good  for  our  purpose." 

"Why  not?" 

"Appears  to  be  dubium  in  it." 

"But  these  people  are  the  largest  producers  of  rock 
in  the  world,  and  do  you  mean  to  tell  me — ?" 

"I  mean  to  tell  you  not  to  use  any  Blue  Mountain 


CHEMICAL    MISERIES 

rock.     It's  the  best  there  is  for  some  purposes,  but 
not  for  us." 

Old  Fatwad  observes  that  Doctor  Noyadont  is 
neither  afraid  nor  uncertain  of  his  ground.  But  he 
likes  to  have  his  way,  and  he  proposes  a  committee 
of  three,  including  Doctor  Noyadont,  to  ascertain. 

"No  occasion  for  me  to  look  it  up  any  more,"  says 
Doctor  Noyadont.  "Go  ahead  and  buy  all  the 
Blue  Mountain  rock  you  want  to,"  he  continues, 
"but  with  it  comes  my  resignation  from  the  board  and 
from  the  office  of  your  consulting  chemist.  Mr. 
Fatwad  expects  your  processes  to  move  on  all  calm 
and  serene  in  the  presence  of  a  catalytic  agent  that 
may  start  up  all  sorts  of  reactions  that  you  don't 
want.  I  can't  be  sure  of  your  product  under  those 
conditions.  If  some  member  of  the  board  were  to 
propose  to  break  the  laws  of  the  State  or  the  nation, 
your  general  counsel  here  would  advise  you  against 
it,  and  if  you  were  to  persist  in  it  he  would  resign. 
Well,  here  you  propose  to  break  nature's  laws  and  ex- 
pect to  keep  out  of  trouble  after  you've  done  it.  I 
call  for  the  question,  Mr.  Chairman,  because  it  in- 
volves a  matter  about  which  we  should  not  be  in  doubt 
for  one  minute.  And  I  offer  my  resignation  now  to 
take  effect  as  soon  as  the  motion  is  carried." 

Mr.  Fatwad  then  withdraws  his  motion.  He  may 
see  a  light,  and  again  he  may  not,  but  the  chances 
are  that  he  will,  because  he  is  nobody's  fool.  But 
rich  men's  vanity  is  one  of  the  most  difficult  things  to 
overcome.  When  it  is  quiescent  it  is  invisible  and 
harmless;  when  it  is  active  it  is  hard  to  endure  and 
highly  dangerous.  The  only  way  to  deal  with  it  when 
it  is  active  is  to  whack  it  on  the  head.  No  employee 
can  do  this  without  providing  for  himself  first  a  good, 
safe  runway  into  the  tall  timber. 

ii 


EVERYMAN'S    CHEMISTRY 

There  should  be  a  chemist  on  the  board  of  every 
corporation  that  has  to  do  with  chemical  processes. 
He  should  be  a  man  of  attainment,  of  distinction,  and 
of  backbone. 

So  much  for  imaginary  conversations.  But  I  could, 
if  I  had  a  mind,  tell  you  true  stories  of  real  men  that 
sound  very  like  them.  Let's  content  ourselves  with  a 
single  one,  drawn  from  life.  It  has  to  do  with  a  great 
corporation  that  was  in  a  bad  way,  especially  troubled 
by  the  ruinous  prices  that  " unprincipled"  competitors 
were  charging  for  wares.  Later  examination  proved 
that  they  were  wasting  several  hundred  thousand 
dollars  annually  from  not  knowing  what  was  actually 
taking  place  among  the  materials  in  their  works.  Their 
men  were  doing  as  they  were  told  with  diligence,  but 
their  materials  were  up  to  mischief.  The  man  in 
authority  replied  to  the  suggestion  that  they  have 
their  plant  examined  by  a  competent  chemical  engi- 
neer that  his  boy  was  a  sophomore  at  Yale  and  was 
taking  up  chemistry  among  his  studies,  "and  so  you 
see,"  he  concluded,  "we  get  all  the  chemistry  we  need." 

This  book  is  written  for  the  man  who  shakes  his 
head  with  the  exclamation  that  he  does  not  know 
anything  about  chemistry  whenever  the  subject  is 
mentioned.  I  have  not  the  ignorant  man  in  mind 
when  I  say  this,  but  one  whose  peregrinations  in  the 
pathways  of  knowledge  have  not  included  the  ways 
of  so-called  inanimate,  but,  in  fact,  very  lively  matter. 
To  make  things  easy,  I  suggest  that  we  take  the  point 
of  view  that  matter,  instead  of  being  inert,  has  ways 
of  its  own,  and  likes  and  dislikes  and  foibles  galore; 
in  short,  that  it  has  personal  qualities.  This  may  not 
be  taking  the  most  exalted  view  of  the  processes  of 
nature,  and  it  is  not  the  fashionable  method  of  teach- 

12 


CHEMICAL   MISERIES 

ing,  but  it  will  be  a  workable  view.  We  need  not 
enter  into  the  problem  of  whether  the  processes  of  life 
are  wholly  of  a  physico-chemical  nature  or  not.  We 
shall  not  study  them  profoundly  or  speculate  upon 
them.  So  far  as  we  are  concerned  and  without  growing 
too  serious  over  it,  let  us  go  the  most  enthusiastic 
vitalists  one  better  and,  finding  motion  in  the  whirling 
atoms  of  the  common  stone,  call  everything  alive. 
Even  a  dead  mouse  can  make  trouble. 

Another  thing  that  has  bothered  me  like  the  voice 
of  conscience  while  planning  this  work  has  been  the 
way  in  which  chemical  undertakings  are  often  organ- 
ized— and  then  fail.  Some  inventor  comes  along  with 
what  seems  like  a  good  idea.  Let's  admit  that  it  is 
a  good  idea.  The  inventor  l<  knows  all  about  chem- 
istry," and  he  is  also  certain  that  other  persons  en- 
gaged in  the  effort  to  produce  the  same  materials  have 
not  seen  the  great  light  that  has  been  revealed  to  him. 
This  great  light  may  be  as  evident  as  that  two  and 
two  make  four,  but  the  inventor  believes  himself  the 
sole  repository  of  the  knowledge.  These  are  danger 
signs,  and  would  be  to  the  wise  manufacturer  the  signal 
to  see  a  competent  chemical  engineer,  get  him  to  look 
up  the  literature,  and  then  possibly  make  a  trip 
somewhere  and  find  out  more  about  it.  He  need 
not  give  the  secret  away,  although  the  chances  are 
ten  to  one  that  a  full  account  of  the  reactions  is  given 
somewhere  in  chemical  literature.  But  let  us  imagine 
that  the  inventor  is  right,  which  is  guessing  against 
odds,  and  imagine  the  company  formed  to  begin 
manufacture.  How  many  chemical  inventors  are 
good  engineers?  They  are  few  and  far  between.  The 
tanks  and  machinery,  the  valves,  pipes,  filter  presses, 
and  what  not  must  be  ordered  and  installed,  and 
we  meet  another  chance  for  failure  because  of  defective 

13 


EVERYMAN'S   CHEMISTRY 

mechanical  construction.  But  let  us  imagine  the 
works  to  be  well  designed  and  the  goods  to  be  pro- 
duced— not  quite  in  measure  and  kind  as  expected — 
but  produced.  Then  comes  the  problem  of  business 
administration,  and  here  people  fail  again.  A  chem- 
ical enterprise  needs  just  as  much  business  ability 
to  operate  it  as  does  any  other.  Why  an  otherwise 
unfortunate  relative  or  friend  out  of  a  job  should  be 
regarded  as  the  very  man  to  undertake  the  business 
management  of  a  new  industry  is  hard  to  understand, 
but  it  is  done  time  and  again.  It  shows  how  hope 
springs  eternal  in  the  human  breast,  but  it  does  not 
prove  wisdom. 

Now  the  thing  to  know  first  in  manufacture  is 
that  a  process  is  right,  not  only  in  glass  in  the  labora- 
tory, but  under  the  entirely  different  conditions  of 
mass  and  surface  and  pressure  in  iron  in  the  works. 
That  is  the  reason  why  it  is  so  wise  to  build  a  test 
plant  first  and  prove  out  every  detail.  The  laboratory 
must  keep  on  the  track  of  the  materials  used  and 
produced  just  as  the  accounting  department  must 
keep  records  of  costs,  and  if  things  go  wrong  the 
chemical  adviser  should  be  called  in,  just  as  he  was 
at  the  start,  and  just  as  the  medical  adviser  is  called 
in  at  the  birth  and  on  the  occasion  of  sickness  of  a 
person. 

Chemical  manufacture  is  not  always  a  difficult  pro- 
cedure. Many  processes  are  by  no  means  so  involved 
as  making  shoes  or  hats  or  furniture — all  of  which 
have  a  chemical  as  well  as  a  mechanical  side.  What 
is  needed  is  a  sense  of  what  is  going  on  inside  of  all 
the  pots,  kettles,  boilers,  and  containers  of  one  sort 
or  another,  and  then  the  same  requirements  hold  good 
that  are  demanded  by  other  industries. 

Of  course,  many  manufacturers  have  their  own 

14 


CHEMICAL    MISERIES 

secret  processes  and  chemical  short-cuts  that  have 
great  value  to  them,  but  it  is  a  fair  guess  that,  of 
chemical  secrets,  at  least  three-fourths  of  them  are 
known  and  are  of  public  record. 

Chemistry  is  not  only  the  intelligence  department 
of  industry;  it  is  everywhere,  and  we  cannot  get 
away  from  it.  Every  kitchen  is  a  laboratory,  every 
baker  is  a  chemical  manufacturer,  and  every  butcher 
is  a  chemical  warehouseman.  Chemistry  washes  us, 
launders  our  clothes,  and  bleaches  and  dyes  them; 
it  provides  us  with  metals,  with  our  morning  paper, 
and  with  books ;  it  helps  the  farmer  to  grow  our  food ; 
and  when  all  is  over,  whether  we  be  burned  to  ashes  or 
buried  in  the  ground,  it  is  by  chemical  processes  that 
our  bodies  go  back  again  into  the  great  order  of  things. 


II 

THE   HEART   OF   THE   THING 

The  World  beyond  the  Microscope  —  The  Nature  of  Matter  —  Atoms 
and  Molecules  —  Speculations  —  The  Middle  of  the  Road  —  The 
Law  of  Avogadro  —  No  Such  Thing  as  Rest  —  Polygamy  in 
Chemistry—  A  Little  Confidential  Talk 


world  beyond  the  microscope  is  as  vast  as 
that  beyond  the  telescope.  We  can  see  and 
feel  a  few  things,  just  a  few,  within  the  very  narrow 
range  of  our  ken,  and  all  the  rest  is  beyond.  We  have 
to  compute  what  we  know  or  what  seems  likely  about 
it.  There  is  a  kind  of  cousinship  between  chemistry 
and  astronomy,  but  their  eyes  are  pointed  in  different 
directions  —  astronomy  has  to  do  with  the  ways  of 
great  masses  of  matter  in  their  movements  through- 
out illimitable  space,  while  chemistry  reasons  about 
and  tries  out  theories  in  regard  to  the  ways  of  parti- 
cles infinitely  small. 

The  study  of  chemistry  is  rather  confusing  in  these 
days,  for  two  reasons.  One  is  that  revelations  are 
coming  so  fast  that  it  is  hard  to  digest  them,  and 
another  is  that  there  has  been  a  grand  wedding  in 
science  within  the  past  few  years  before  the  war.  Phys- 
ics and  chemistry  have  been  joined  together  in  such 
intimacy  that  it  is  hard  to  tell  where  one  begins  and 
the  other  ends.  And  higher  mathematics  has  entered 
into  the  union,  so  that  chemistry  to-day  has  become 

16 


THE   HEART   OF   THE   THING 

almost  as  mathematical  a  science  as  is  astronomy  or 
physics. 

Now  we  shall  not  enter  into  problems  of  mathe- 
matics or  of  physics.  I  shall  not  even  attempt  to 
tell  you  how  computations  are  made,  for  one  reason 
because  it  would  make  the  book  dull  reading  to  those 
who  are  not  mathematicians,  and  for  another  reason 
because  I  couldn't  if  I  tried. 

Let  us,  nevertheless,  enter  into  a  little  discussion 
as  to  the  nature  of  matter.  In  Athenian  days  it  was 
a  popular  debate  among  the  Sophists  whether,  if  a 
particle  of  matter  were  divided  and  one  of  its  pieces 
divided  again,  and  one  of  them  divided  again,  and  so 
on  and  on,  granted  infinite  vision  and  infinite  refine- 
ment of  work,  an  indivisible  particle  would  ever  be 
reached.  In  mathematics  one  divided  by  infinity 
equals  zero.  In  chemistry  the  name  of  this  ultimate 
particle  on  which  the  Greeks  speculated  was  taken 
and  applied  to  the  smallest  particle  of  any  one 
element  that  combines.  The  atom  has  ceased  toi 
be  the  smallest  particle  imaginable,  but  it  is  the\ 
smallest  unit  of  substance  that  we  can  conceive  of 
any  element. 

We  must  get  this  idea  of  atoms  and  molecules  and 
elements  clear  in  our  minds,  for  I  shall  keep  talking 
about  them  constantly,  and  I  know  very  well  what 
will  happen  to  this  book  if  I  do  not  make  it  clear  to 
you.  So  let  us  imagine  all  matter  to  constitute  a  very 
odd  world  of  mankind.  Then  the  eighty-odd  elements 
would  be  the  different  races,  some  of  them  very  wide- 
spread and  some  of  them  very  rare  and  hardly  known. 
Now  let's  call  the  atoms  the  individual  persons  of 
each  race.  Then  there  will  be  eighty-odd  different 
kinds  of  atoms,  some  heavy  and  some  light,  some  one 
color  and  some  another,  according  to  the  race  or  ele- 

17 


i 


EVERYMAN'S   CHEMISTRY 

ment  to  which  they  belong.    But  all  the  atoms  of  any 
one  element  will  have  the  same  qualities. 

The  individual  atoms  do  not  get  born  and  die  as 
we  do ;  they  live  right  on.  Do  not  think  about  radium 
or  radio-active  elements;  call  that  a  skeleton  in  the 
closet  and  close  the  closet  door.  The  individuals 
or  atoms  have  no  sex,  but  they  mate  up  in  pairs  or 
/  larger  numbers,  in  what  we  might  call  families.  The 
;  families  are  molecules.  There  is  a  great  deal  of  race 
prejudice  both  ways,  in  favor  of  mating  or  grouping 
and  against  it,  among  the  elements  or  races.  Atoms 
of  two  elements  that  will  not  combine  themselves 
may  be  induced  to  join  in  a  large  molecule  of  many 
j  atoms  of  other  elements.  Atoms  are  nearly  always 
bund  in  families  or  molecules ;  there  are  no  bachelors 
or  old  maids,  except  in  certain  metals  in  a  gaseous 
condition  and  in  the  rare  gases  of  the  air,  like  argon, 
krypton,  etc.,  and  let  us  not  think  about  them.  We 
say  sometimes  that  the  family  is  the  unit  of  society, 
and  it  often  takes  more  than  a  little  faith  to  believe 
it.  When  we  say  that  the  molecule  is  the  unit  of 
stuff  we  are  nearer  the  truth.  The  atoms  often  wander 
from  one  family  or  molecule  to  another,  sometimes 
singly  and  sometimes  in  groups;  and  sometimes  they 
do  this  with  explosive  violence,  while  at  others  they 
are  interminably  slow  in  getting  settled.  The  wan- 
dering of  atoms  from  one  molecule  to  another  is  what 
we  call  a  chemical  reaction. 

It  is  all  imaginary,  all  theory,  and  yet  it  is  the 
basis  of  chemistry.  It  was  said  in  some  verses  called 
"Rollo  and  His  Uncle  in  Chemistry,"  at  a  meeting 
of  chemists,  that 

1  You'd  better  join  the  church  before  this  course  is  well  begun, 
Because  you'll  need  to  exercise  the  art  of  faith,  my  son. 

18 


THE   HEART   OF   THE   THING 

While  we  are  discussing  the  nature  of  matter,  we 
might  as  well  enter  a  little  way  into  the  pleasant  fields 
of  speculation  about  it.  For  years  we  have  taken  it 
for  granted  that  matter  is  indestructible.  Well,  is  it 
indestructible?  Is  the  cosmic  universe  bounding 
along,  combining  elements  into  molecules  of  eternal 
atoms  and  then  dissociating  them  in  a  kind  of  ring- 
around-o'-rosy  without  any  change  except  such  mere 
incidents  as  the  drying  up  of  this  planet  and  the 
birth  of  another?  Are  the  elements  really  elemental? 
Are  they  primeval  stuff?  They  may  be,  but  they 
hardly  seem  so.  You  will  observe  later  how  closely 
related  to  one  another  certain  of  these  elements  are, 
and  it  would  seem  that  at  least  those  that  are  closely 
related  have  a  common  origin.  And  why  are  some  of 
them  always  found  together? 

Then  there  is  radium.  It  gives  off  constantly  a 
series  of  rays  with  a  power  beyond  any  force  known 
to  us.  Whence  comes  this  energy?  And,  again,  be- 
sides these  rays  it  gives  forth  an  emanation  which 
seems  distinct  from  its  rays,  and  which,  by  itself,  de- 
composes into  a  radio-active  solid  and  helium  gas. 
Helium  is  an  element.  Radium  is  an  element,  and 
yet  a  part  of  radium  becomes  helium.  Here  is  a  fact. 
The  theory  that  matter  is  indestructible  is  not  so 
certain,  after  all. 

And  this  is  not  all.  Combinations  of  elements  are 
usually  more  stable  than  the  elements  are  by  them- 
selves. Two  parts  by  volume  of  hydrogen  gas,  which 
they  use  to  fill  balloons  because  of  its  lightness,  and 
one  part  by  volume  of  oxygen,  a  gas  which  is  one- 
fifth  of  the  air,  produce  water.  In  its  whole  nature 
water  is  something  entirely  different  from  either  of 
its  component  parts — less  like  them  than  other  ele- 
ments are,  It  has  ways  of  its  own,  just  as  elements 

19 


EVERYMAN'S   CHEMISTRY 

have.  Why,  then,  just  because  elements  cannot, 
with  the  means  we  have,  be  divided  into  other  bodies, 
should  we  claim  immortality  for  them? 

Now  let  us  take  another  point  of  view.  Imagine, 
please,  a  point  of  space.  Not  an  atom;  let's  give  the 
atom  credit  for  considerable  size.  Of  course,  it's 
beyond  the  microscope,  but  because  it's  smaller  than 
a  wave  of  light  is  no  reason  why  we  should  call  it 
zero.  Let's  call  it  large;  there's  room  enough.  This 
point  of  space  that  we  are  imagining  is  not  a  speck; 
it  is  just  a  center  of  force.  It  is  a  charge  of  electricity. 
Whether  it  shall  have  substance  or  not  is  according 
to  your  pleasure.  I  think  the  more  usual  opinion  is 
that  it  has  no  substance,  but  if  it  disturbs  you  to 
think  of  it  in  this  connection  you  might  call  it  primary 
stuff  as  long  as  you  think  it  necessary  to  do  so.  That 
point  of  space  is,  let  us  say,  charged  positively  with 
electricity.  Around  and  about  it  whirl  other  points 
or  centers  of  force,  charged  negatively.  These  are 
called  electrons.  They  pass  the  energy  along  the 
surface  of  wires  when  telegraphic  messages  are  sent. 
The  atom  of  hydrogen,  supposed  to  be  the  smallest 
atom  of  all,  is  seventeen  hundred  times  greater  than  an 
electron.  Doctor  Crehore,  of  Yonkers,  who  is  a 
great  mathematician,  has  computed  the  atoms  of  a 
number  of  elements  as  systems  of  electrons  positively 
and  negatively  charged,  revolving  in  their  respective 
orbits  very  much  as  solar  systems,  and  providing  free 
energy  to  give  to  atoms  all  their  combining  qualities. 
The  difference  in  the  organization  of  these  infinitely 
small  solar  systems  would  account  for  the  differences 
between  the  elements. 

This  makes  every  atom  itself  a  solar  system. 
Whirling  units  of  force,  persevering  in  their  orbits  so 
that  we  cannot  break  them  apart,  but  definite  and 

20 


THE   HEART   OF   THE   THING 

indestructible  only  because  our  vision  is  so  weak, 
our  powers  so  frail,  and  our  lives  so  short.  They  will 
not  always  persevere.  They  will  change.  Nothing  is 
permanent,  nothing  immutable,  nothing  is  real 
throughout  the  ages. 

Strange,  how  we  revert  to  the  philosophy  of  Bishop 
Berkeley  and  the  wise  sayings  of  the  East,  and  wel- 
come them  as  the  fashion  for  our  thoughts  again — 
for  a  season. 

But  let  us  get  back  to  the  middle  of  the  road,  to 
more  concrete  things.  Please  believe  that  atoms  can- 
not be  divided.  This  is  the  working  hypothesis.  We 
find  in  practice  that  the  elements  cannot  be  split-up 
into  other  bodies.  Iron  stays  iron,  gold  remains 
gold,  and  the  same  holds  true  of  all  of  them  for  all 
practical  purposes.  They  combine  with  one  another 
in  definite  proportions.  They  not  only  mix,  they 
combine  and  produce  entirely  different  bodies.  Bring 
two  elements  that  have  a  liking  for  each  other  to- 
gether, and  just  so  much  of  the  one  will  combine  with 
just  so  much  (but  not  an  equal  weight)  of  another. 

Here  let  us  consider  another  interesting  postulate 
called  the  law  of  Avogadro.  All  gases  at  the  same  J 
temperature  and  pressure  contain  the  same  number  { 
of  molecules  within  the  same  volume.  More  con- 
cretely stated,  there  are  the  same  number  of  mole- 
cules in  a  cubic  inch  of  one  gas  that  there  are  in  a 
cubic  inch  of  another,  provided  the  temperature  and 
the  pressure  are  the  same.  Of  course,  the  molecules  of 
one  gas  differ  from  those  of  another  in  size  and  weight, 
but  in  a  gas  they  are  far  apart,  anyway,  and  they  are 
supposed  to  be  flying  about  all  the  time  like  so  many 
balloons,  hitting  one  another  and  bounding  back  again 
until  they  strike  something  else,  and  then  they  bound 
off  in  another  direction,  for  they  are  supposed  to  be 

21 


EVERYMAN'S    CHEMISTRY 

very  elastic.  There  is  nothing  to  impede  them  in 
their  flight  through  space  except  either  the  walls  that 
inclose  them  or  other  molecules.  It  makes  no  differ- 
ence whether  they  are  molecules  of  elements  or  of 
combinations;  they  all  behave  in  the  same  way. 
Now  I  think  you  will  understand  what  happens  when 
you  compress  a  gas;  there  is  such  a  bombardment 
of  molecules  against  the  walls  of  the  container  that 
your  apparatus  will  run  hot.  Keep  up  the  pressure, 
increase  it,  and  cool  your  apparatus,  and  the  gas  will 
turn  into  a  liquid.  Cooling  slows  down  the  motions 
of  the  molecules;  heating  increases  it.  Then  cool  the 
liquid  still  more  and  it  will  freeze  or  turn  to  a  solid. 
Some  of  the  freedom  of  movement  which  the  mole- 
cules had  in  the  liquid  form  is  lost ;  in  some  way  they 
seem  to  clinch — and  there  is  the  solid.  They  are  not 
still  in  the  solid,  but  their  movements  are  much  more 
circumscribed. 

In  all  the  chemical  world  there  is  no  such  thing  as 
rest  and,  except  as  we  may  speculate  upon  it,  no  such 
thing  as  death. 

Chemically  speaking,  then,  nature  has  about  eighty 
kinds  or  races  of  matter  called  elements,  and  every- 
thing there  is  in  nature  is  made  up  of  them.  They 
enter  into  combinations  with  one  another  and  produce 
bodies  that  sometimes  show  a  family  resemblance, 
but  more  often  are  totally  unlike  the  stuffs  that  they 
are  made  of.  They  are  given  to  polygamy  and  poly- 
andry as  matters  of  entire  propriety ;  and  if  it  were  not 
for  the  fact  that  we  cannot  imagine  atoms  as  having 
sex,  the  way  they  shift  about  in  their  matings  would 
scandalize  any  community.  They  have  rules  and 
ways  of  their  own,  according  to  the  deductions  and 
findings  of  wise  and  observant  men,  and  then  again 
they  appear  to  break  them.  Therefore  chemistry 

22 


THE    HEART   OF   THE   THING 

is  a  study  accompanied  by  constant  surprises,  and 
the  only  authority  who  " knows  all  about  chemistry" 
is  a  poor  creature,  bereft  of  imagination.  There  are 
vast  domains  in  the  subject  as  yet  undiscovered, 
and  without  doubt  some  of  the  favorite  hypotheses 
of  to-day  will  fall  by  the  wayside  to-morrow.  But 
you  do  not  have  to  know  all  of  human  nature  to  be- 
come interested  in  persons,  and  for  the  same  reason 
you  do  not  have  to  read  deeply  into  this  subject  before 
its  romantic  side  will  begin  to  appear.  If  it  does  not 
show  itself  to  you,  the  fault  will  be  mine,  for  I  assure 
you  the  romance  is  there. 

You  need  not  try  to  learn  anything  by  heart. 
There  is  an  ample  index  to  what  is  said,  and  I  have 
no  desire  to  put  the  burden  of  memorizing  upon  you. 
The  task  that  I  have  set  myself  is  to  keep  you  inter- 
ested as  you  read  along,  and  if  I  succeed  in  this  I 
have  a  feeling  that  you  will  want  to  look  things  up 
for  yourself,  for  the  chemical  view  of  things  is  very 
fascinating,  and  it  takes  in  all  the  processes  of  nature 
and  something  of  nearly  all  the  industries  of  man. 
In  fact,  I  shall  confess  frankly  that  I  am  after  some- 
thing of  yours  that  is  not  included  in  the  money  you 
pay  for  this  book — I  am  after  your  curiosity.  If  I 
can  get  that,  there  will  be  no  holding  you  back  from 
the  subject. 

Please  do  not  be  frightened  if  you  see  some  chemical 
formulas  that  appear  bewildering  farther  along  in 
the  later  pages.  I  do  not  think  they  will  worry  you, 
if  you  will  only  wait  until  you  come  to  them.  The 
whole  work  is  designed  as  a  man's  book  rather  than 
as  a  torment  for  the  nursery,  and  so  I  have  not  hesi- 
tated to  enter  into  some  of  the  profounder  problems. 
But  if  we  only  keep  good-natured  about  them  there 
is  no  reason  why  they  should  be  dull. 

3  23 


Ill 

PHASES    OF   MATTER 

Solids,  Liquids,  and  Gases — The  Ways  of  Gases — Solutions — Ions 
and  the  Ionic  Theory — An  Electric  Battery — Solvents  and  So- 
lutes— Solid  Solutions — Colloids — Difference  between  Colloidal 
Particles  and  Molecules — 35,000,000,000  Miles  out  of  a  Cubic 
Inch 

WE  must,  in  order  to  make  a  reasonable  start, 
go  over  a  few  points  in  regard  to  the  conditions 
of  matter.  It  is  subject  to  three  states — solid,  liquid, 
and  gaseous.  Water,  for  instance,  is  liquid  at  what 
we  call  ordinary  temperature,  solid  ice  in  the  cold, 
and  steam  vapor  in  heat.  Most  bodies  are  subject  to 
these  three  phases  at  different  temperatures  and  dif- 
ferent pressures,  although  some  go  over  from  the  solid 
to  the  gaseous  state  almost  without  entering  the 
liquid  phase.  They  sublimate.  Iodine  is  a  familiar 
example. 

If  we  imagine  the  molecules  as  each  one  an  indi- 
vidual kind  of  a  balloon,  and  all  of  them  bobbing 
around  loose,  with  nothing  to  hold  them  together 
but  as  though  striving  to  keep  as  far  as  possible  from 
one  another,  they  are  in  the  state  of  a  gas.  If  we 
imagine  them  as  skipping  around  every  which  way 
over  and  under  one  another,  sideways,  forward,  and 
backward,  but  held  down  by  a  greater  tension,  we 
may  say  that  the  body  which  they  constitute  is  in  a 
liquid  state.  When  they  clinch  we  have  a  solid. 

24 


PHASES   OF   MATTER 

Even  then  they  continue  in  motion,  dancing  around 
all  the  time. 

We  have  spoken  of  the  law  of  Avogadro,  whereby 
it  is  held  that  at  equal  temperature  and  pressure  all 
gases  contain  the  same  number  of  molecules  within 
the  same  volume.  We  note  that  the  molecules  are 
in  constant  motion  and  that  their  bombardment  of 
the  walls  of  the  container  is  what  causes  gas  pressure. 
Now  let  us  imagine  the  walls  to  be  absolutely  elastic, 
so  that  they  give  way  to  pressure  without  opposition. 
Then  for  every  degree  centigrade  that  any  gas  is 
heated,  without  any  increase  of  pressure  from  the 
outside  its  volume  will  increase  1/273  part,  and  the 
container  will  increase  in  size  just  1/273  of  its  whole. 
And  for  every  degree  centigrade  that  we  cool  it,  it 
will  contract  just  that  much — 1/273  °f  its  volume. 
That  is  the  measure  of  the  drive  of  a  gas  against  the 
walls  of  a  container  when  you  heat  it.  This  is  why  a 
boiler  bursts;  its  walls  are  not  sufficiently  elastic. 
And  if  you  take  an  inclosed  vessel  of  air  or  any  other 
gas  at  room  temperature  and  pressure  and  cool  it 
within  the  container,  the  pressure  will  be  from  the 
outside  in,  because  the  ordinary  pressure  of  the  air 
upon  everything  is  about  fifteen  pounds  to  the  square 
inch,  while,  if  you  heat  it,  the  pressure  will  be  from 
the  inside  toward  the  outside.  The  temperature  of 
—273°  C.  is  held  to  be  the  absolute  zero  at  which  no 
gas  can  exist  as  such;  it  will  be  liquid  or  solid.  Do 
not  forget,  however,  that  the  molecules  are  always  in 
motion;  more  lively  in  heat  than  in  cold,  moving 
faster  and  with  greater  push. 

Now  let  us  take  a  liquid,  say  water,  and  put  into 
it  some  common  salt,  which  straightway  disappears. 
We  say  it  has  gone  into  solution.  These  particles, 
the  molecules  of  salt,  are  there  swimming  around. 

25 


EVERYMAN'S    CHEMISTRY 

They  spread  themselves  throughout  all  the  water 
that  is  available.  If  we  conduct  a  current  of  elec- 
tricity through  the  solution,  some  of  the  salt  mole- 
cules will  decompose,  and,  being  made  up  as  they  are 
of  chlorine  and  sodium,  the  one  element  will  hasten  to 
the  positive  pole  and  the  other  to  the  negative  one. 
Now  water  alone,  pure  water,  will  not  conduct  elec- 
tricity, but  water  containing  salt  or  sulphuric  acid 
or  caustic  soda  or  any  other  electrolyte  will  conduct 
it.  Those  bodies  which  dissolve  in  water  and  whose 
molecules  split  up  when  a  current  of  electricity  is 
I  passed  through  are  called  electrolytes. 

Here  we  may  as  well  consider  the  ionic  hypothesis, 
which  is  one  of  those  things  that  is  very  possibly  not 
so,  or  only  partially  true,  and  yet  it  is  well  to  believe 
it,  so  as  to  get  at  the  chemical  view  of  what  happens. 
To  quote  from  the  Rollo  verses  again: 

I  used  to  think  theology  was  rather  hard  on  doubt, 
But  chemistry,  with  ions,  beats  theology  all  out. 

Now  please  take  a  fresh  grip  upon  this  subject; 
let's  go  at  it  from  another  angle  of  vision.  We  have 
to  do  this  constantly  in  chemistry.  Some  of  the  mole- 
cules of  salt,  on  going  into  solution  and  without  the 
need  of  our  conducting  a  current  of  electricity  through 
it,  dissociated  into  free  chlorine  and  free  sodium  atoms 
in  solution,  each  charged  with  opposite  electrical 
charges.  Let  us  say  they  obtained  their  electrical 
charges  from  the  force  which  held  them  together  in 
the  salt.  In  this  state  the  dissociated  parts  of  mole- 
cules are  called  ions.  The  freedom  of  these  charged 
atoms  or  ions  is  not  so  great,  after  all;  there  is  no 
such  thing  as  free  electricity,  so  the  ions  with  a  posi- 
tive and  those  with  a  negative  charge  are  perfectly 
balanced.  There  is  an  equal  number  of  each  sort, 

26 


PHASES    OF    MATTER 

They  are  in  equilibrium.  We  have  to  suppose  that 
these  positively  and  negatively  charged  atoms  or  ions 
behave  very  differently  from  the  same  atoms  or  parts 
of  molecules  when  they  cease  to  be  ions  —  that  is, 
when  they  have  given  up  their  electric  charges.  This 
statement  may  not  be  of  thrilling  interest  at  this 
point,  but  we  must  get  it  recorded. 

When  we  put  a  very  little  salt  into  a  great  deal  of 
water,  thus  making  a  very  dilute  solution,  it  appears 
that  all  of  the  solute  or  salt  becomes  ionized ;  we  have 
only  -water  and  chlorine  and  sodium  ions.  As  soon 
as  we  make  it  more  concentrated,  only  a  part  of  the 
salt  becomes  ionized,  and  this  proportion  decreases 
as  the  solution  becomes  more  concentrated.  It  is  all 
theory,  pure  theory,  and  yet  later  on  you  will  see  how 
useful  it  is.  It  would  not  do  to  say  that  these  ions, 
these  free  atoms  with  electric  charges,  are  the  same  as 
ordinary  atoms  of  chlorine  and  sodium,  because  if  they 
were  we  should  have  caustic  soda  and  free  chlorine 
as  the  result  of  putting  salt  into  water.  So  we  say 
that  the  ions  are  so  perfectly  balanced  with  positive 
and  negative  charges  that  nothing  happens,  so  far 
as  we  can  see. 

Then  suppose  you  ask  why  it  is,  with  free  atoms  of 
chlorine  with  a  negative  charge  and  of  sodium  with  a 
positive  charge  swimming  around  loose,  that  they 
don't  combine  right  up  again  to  chloride  of  sodium 
or  salt,  with  all  that  free  energy?  I  believe  the  clas- 
sical answer  to  such  questions  is  that  you  are  too 
young,  too  immature,  to  understand  these  things. 
But  the  fact  is  that  it  has  not  been  answered  in  any 
satisfactory  way. 

Sulphuric  acid  is  another  well-known  electrolyte, 
and  the  formula  for  sulphuric  acid  being  H2SO4  (two 

27 


EVERYMAN'S    CHEMISTRY 

atoms  of  hydrogen,  one  of  sulphur,  and  four  of  oxy- 
gen), we  find  that  it  dissociates  as  follows: 


H2SO4  =  2H  +  SO4. 

But  note  that  these  two  hydrogen  atoms  and  the 
SO4  group  are  oppositely  charged  with  electricity. 
Suppose,  then,  we  put  into  a  jar  a  solution  of  dilute 
sulphuric  acid  and  dip  into  the  jar  two  electrodes  — 
say,  one  of  zinc  and  one  qf^graphite,  connected  with 
each  other  by  wire.  The  SO4  ions  will  wander  over 
to  the  zinc,  pull_its  molecules  apart,  take  an  atom 
of  zinc  for  every  SO4  ion,  and  proceed  to  shape  itself 
up  into  molecules  of  zinc  sulphate,  or  ZnSO4.  (Zn 
is  zinc;  it  has  two  bonds  or  units  of  combining  power, 
so  that  one  atom  of  zinc  takes  the  place  of  two  of 
hydrogen.)  The  two  hydrogen  ions  wander  over  to 
the  other  pole,  and,  being  unable  to_combine  with  the 
graphite  for  lack  of  affinity,  and  the  SO4,  to  which  they 
were  formerly  attached  as  sulphuric  acid,  H2SO4, 
being  already  settled  down  with  the  zinc  as  zinc 
sulphate,  ZnSO4,  they  do  what  lone  ions  always  do, 
if  there  is  an  electrode  around.  As  soon  as  each  hydro- 
gen ion  touches  the  graphite  electrode  it  gives  up  its 
charge  and  becomes  plain  hydrogen  again.  There  is 
nothing  in  the  solution  for  it  to  combine  with,  and 
so,  being  a  very  light  gas,  its  atoms  couple  up  to 
molecules  and  it  escapes  into  the  air. 

Now  we  have  made  sulphate  of  zinc  and  produced 
free  hydrogen  in  our  reaction,  but  we  have  done  some- 
thing else.  As  soon  as  we  have  connected  those  two 
electrodes  of  zinc  and  graphite  each  with  a  copper 
wire  and  connected  the  wires  with  a  small  electric 
lamp,  we  find  that  the  lamp  glows  with  light,  showing 
that  an  electric  current  is  passing  through.  And  the 

28 


PHASES    OF    MATTER 

current  comes  from  the  charge  given  up  by  the  hydro- 
gen ions  where  they  have  touched  the  graphite  elec- 
trode, just  as  its  atoms  coupled  up  to  molecules  and 
escaped  as  plain  hydrogen  gas.  On  the  other  side  it 
came  from  the  zinc  electrode  just  as  the  SO4  ions 
touched  it  and  gave  up  their  opposite  charge  as  they 
combined  with  the  zinc  to  produce  zinc  sulphate,  ZnSO4. 

Suppose  the  zinc  and  graphite  electrodes  had  not 
been  connected  with  each  other  by  a  wire.  Then 
they  would  not  have  been  electrodes ;  they  would  have 
been  just  a  stick  of  zinc  and  a  stick  of  inert  carbon 
dipped  into  the  solution.  The  sulphuric  acid  would 
simply  attack  the  zinc  and  give  up  hydrogen  at  the 
zinc.  The  word  ion  means  traveler,  and  the  hydrogen 
ions  would  not  have  traveled  over  to  the  graphite 
and  given  up  their  charge  over  there  if  there  had 
been  no  connection  of  one  pole  with  the  other. 

I  hope  the  ionic  theory  will  not  prove  a  nuisance 
to  you  or  discourage  you  at  this  point.  We  need  to 
have  an  idea  of  it  in  our  minds  because  it  is  the  foun- 
dation of  electrochemistry.  Let  us  reverse  the  opera- 
tion and  run  an  electric  current  through  a  solution 
of  a  salt  of  a  metal.  In  this  instance  the  dissociated 
metal  ions  strike  the  electrode,  give  up  their  electric 
charge,  and,  being  unable  to  escape  into  the  air 
because  they  are  solid  at  ordinary  temperatures,  they 
plaster  themselves  as  molecules  right  upon  the  elec- 
trode. This  is  the  basis  of  electroplating,  and  is  the 
principle  of  the  electrolytic  refining  of  copper  and 
other  metals. 

We  may  add  a  crystalline  body  to  hot  water  until 
we  have  more  in  solution  than  will  stay  there  when 
the  water  cools.  Then  the  excess  will  crystallize  out 
in  regular,  mathematically  correct  forms,  according  to 
its  own  form  of  crystals.  We  can  test  and  measure 

29 


EVERYMAN'S    CHEMISTRY 

just  how  soluble  any  crystalline  body  is  in  any  liquid 
at  a  given  temperature  and  pressure.  The  liquid  is 
called  the  solvent,  and  the  body  dissolved  is  called 
the  solute. 

So  intimately  related  are  solvent  and  solute  that 
they  may  almost  seem  to  be  a  chemical  combination; 
but  they  are  not.  A  chemical  combination  is  a  defi- 
nite thing — so  many  atoms  of  one  element  with  so 
many  atoms  of  one  or  more  others,  and  their  pro- 
portions are  fixed.  A  solution  is  not  fixed  in  its  rela- 
tions of  solute  to  solvent;  the  proportions  may  vary 
from  a  trace  of  the  solute  to  a  saturated  solution  that 
will  not  contain  any  more. 

Now  suppose  instead  of  taking  water  we  melt  a 
metal  and  dissolve  another  metal  in  it.  We  can  get 
a  complete  solution  with  the  same  relation  of  solvent 
to  solute  in  all  the  parts.  But  just  as  with  water,  the 
solvent  may  not  be  able  to  dissolve  as  much  of  the 
solute  metal  when  it  cools  off  as  it  did  when  it  was 
molten  and  hot,  and  then  you  can  see  the  excess  of 
the  solute  oozing  out  as  it  cools  off.  The  one  will 
dissolve  in  the  other  up  to  saturation,  but  no  more. 
When  it  cools  off  we  have  what  is  known  as  a  solid 
solution,  and  here  is  one  of  the  sportiest  fields  of 
modern  chemistry. 

For  instance,  when  you  buy  steel  you  buy  it  for  a 
certain  purpose.  You  want  it  to  be  hard  or  soft  or 
resilient  or  to  be  chemically  resistant,  or  you  may  want 
it  to  give  a  good  cutting  edge  or  to  have  some  other 
quality.  The  demand  is  growing  in  the  steel  industry 
for  special  products  for  special  purposes.  The  buyer 
is  growing  wise.  He  is  interested  in  endurance  and 
in  the  quality  of  his  product  in  the  interest  of  the 
Greater  Economy  whereby  his  business  may  keep  him 
for  long  rather  than  for  a  short  time.  Solutions  of 

30 


PHASES   OF   MATTER 

rare  and  common  metals  added  to  steel  even  in  very 
small  quantities  give  special  and  particular  qualities. 

Again,  let  us  take  a  substance  like  gum  arabic, 
that  is  without  form  and  that  will  mix  with  its  sol- 
vent in  any  relation,  that  does  not  crystallize  and  that 
will  dissolve  and  dissolve  until  a  thick  paste  is  reached. 
Then  we  have  a  different  situation.  Such  a  non- 
crystalline  body  is  called  a  colloid,  and  its  relation  to 
its  solvent  is  not  the  same  as  that  of  a  crystalline  body. 

Many  insoluble  solids,  as,  for  instance,  gold,  will 
enter  into  colloidal  solution  if  the  particles  are  in  a 
sufficiently  fine-divided  state.  A  colloidal  solution 
of  gold  in  water,  which  requires  both  art  and  chemical 
chicanery  to  prepare,  is  a  red  liquid,  and  the  particles, 
if  sufficiently  finely  divided,  will  not  precipitate  upon 
the  bottom  of  the  vessel. 

Colloids  have  ways  of  their  own  that  are  very 
remarkable.  If  a  drop  of  a  colloidal  solution  of  gold 
or  a  drop  of  very  dilute  skim  milk  is  observed  under 
an  ultra-microscope,  the  colloidal  particles  will  be 
observed  to  be  constantly  and  forever  dancing  around. 
They  are  never  still  until  a  reagent  is  brought  in  which 
clots  them.  This  motion  is  called  the  Brownian  move- 
ment. 

I  can  do  no  better  on  this  subject  than  to  give  some 
notes  that  I  took  at  a  lecture  on  colloid  chemistry 
given  by  Prof.  Wilder  D.  Bancroft,  of  Cornell  Uni- 
versity, delivered  at  a  public  meeting  of  the  American 
Chemical  Society  in  September,  1916.  It  would  not 
be  fair  to  Doctor  Bancroft  to  hold  him  responsible 
for  the  letter  of  my  transcript.  I  do  not  know  short- 
hand, and  this  is  mostly  what  I  remember  of  his  talk : 

Formerly  it  was  held  that  a  substance  was  col- 
loidal as  distinguished  from  those  that  would  crystal- 
lize. A  better  definition  is  that  of  the  colloidal  state, 


EVERYMAN'S    CHEMISTRY 

which  has  to  do  with  substances  divided  into  very 
small  particles — not  molecules  or  atoms,  but  still  very 
small.  It  is  the  chemistry  of  grains,  drops,  bubbles, 
filaments,  and  films.  It  touches  every-day  life  and 
industry — cement,  brick,  pottery,  varnish,  soap,  rub- 
ber, milk,  butter,  purification  of  water,  sewage,  pho- 
tography, the  great  domain  of  physiology,  and  then 
a  lot  more. 

Very  fine  particles  have  a  greater  proportion  of  sur- 
face to  mass  than  larger  particles,  and  every  surface  can 
condense  other  things  upon  it.  For  instance,  Doctor 
Cushman  found  in  working  on  cements  that  if  he  got 
his  cement  ground  to  a  sufficiently  fine  powder  it  ran 
like  water.  The  reason  was  the  adhesion,  or  adsorp- 
tion, as  it  is  called,  of  a  thin  film  of  air  around  each 
particle.  Every  grain  had  something  like  a  pneumatic 
tire  surrounding  it,  and  so  they  all  ran  easily. 

If  you  break  a  piece  of  china,  the  pieces  will  not 
stick  together  well  because  of  the  air  film  on  the 
broken  surfaces.  Jerome  Alexander  finds  that  split 
pieces  of  mica  will  coalesce  immediately  after  being 
broken,  but  if  left  to  stand  awhile  they  will  not.  To 
adsorb  the  air  film  takes  time. 

It  is  hard  to  make  two  soap  bubbles  coalesce,  be- 
cause of  the  air  films  upon  their  surfaces.  Sir  William 
Thomson  found  that  dried  oatmeal  takes  on  water 
by  this  same  process;  that  it  takes  up  as  much  water 
as  sulphuric  acid  does. 

Dyed  fabrics  are  those  in  which  to  every  fiber  of  the 
fabric  there  adheres  a  film  of  the  dyestuff. 

So-called  "acid  soils,"  if  washed  out  with  water, 
will  not  give  an  acid  reaction  to  the  water;  but  if 
wet  litmus  paper  is  pressed  upon  the  soil,  the  paper 
turns  red.  This  is  because  the  soil  adsorbs  some- 
thing alkaline  from  the  litmus  paper,  leaving  some- 

32 


PHASES   OF   MATTER 

thing  acid  to  predominate  and  thus  turn  the  paper 
red.  So,  whether  the  soil  is  properly  called  acid  or 
not  is  a  problem  in  the  philosophy  of  Tweedledum 
and  Tweedledee,  which  he  could  best  explain  by  the 
parable  of  the  bananas.  Suppose  he  were  to  leave  a 
large  assortment  of  both  red  and  yellow  bananas  on 
his  desk  and  then  leave  the  room.  On  his  return  he 
finds  many  more  yellow  bananas  than  red  ones, 
whereas  before  he  had  to  all  appearances  as  many  of 
one  kind  as  of  the  other.  Then  the  problem  to  de- 
termine is  whether  some  kind  friend  has  secretly  pre- 
sented him  with  an  armful  of  yellow  bananas  to  add 
to  his  store,  or  the  more  likely  contingency  that  some- 
body else  has  made  away  with  some  of  the  red  ones. 

The  reasons  why  minute  colloidal  particles  remain 
in  solution  are,  first,  because,  being  covered  by  a 
film  of  something  that  keeps  them  apart,  they  don't 
join.  Then,  looking  at  a  colloidal  solution  through 
an  ultra-microscope,  one  sees  the  particles  constantly 
dancing  about  in  their  perpetual  quadrille — the 
Brownian  movements,  as  stated  above.  But  why  do 
they  dance?  The  answer  may  be  found  in  the  com- 
parison of  a  floating  chip  with  a  floating  ship.  The 
little  ripples  cause  the  chip  to  be  engaged  in  very- 
lively  tossing  and  pitching,  whereas  the  ship  stands 
still.  For  the  same  reason,  the  colloidal  particles, 
bombarded  as  they  are  by  the  molecules  of  the  sol- 
vent, dance  about  constantly.  If  the  particles  are 
large  enough,  although  the  bombardment  keeps  up, 
they  are  not  moved  by  it. 

If  the  protective  film  which  covers  the  particles  be 
removed  by  a  chemical  reagent  which  dissolves  it  or 
precipitates  it,  then  the  particles  will  accumulate  in 
groups,  their  motion  ceases,  and  they  sink  or  rise 
according  to  their  weight.  They  coagulate.  On  the 

33 


EVERYMAN'S    CHEMISTRY 

other  hand,  if  all  the  finely  divided  particles  of  a  col- 
loidal solution  should  have  a  negative  electric  charge, 
they  will  repel  one  another  and  remain  suspended. 
The  same  holds  true  if  all  should  have  a  positive 
charge.  Alternating  currents  of  high  frequency  will 
often  cause  them  to  coalesce  and  fall  down,  while 
direct  currents  of  very  high  frequency,  such  as  are 
used  in  the  Cottrell  process,  drive  them  upon  the 
baffle-plates  set  to  catch  them. 

Here  end  my  notes  on  Doctor  Bancroft's  lecture. 

The  line  between  colloid  chemistry  and  the  chem- 
istry of  crystalline  substances  is  not  at  all  clear. 
Indeed,  likely  as  not  the  distinctions  now  made  are 
greater  than  are  warranted.  We  can  see  by  the  ultra- 
microscope  the  light  reflected  by  colloidal  particles. 
We  cannot  do  this  with  molecules.  By  computation, 
it  is  said  that  forty  million  molecules  of  a  gas,  ranged 
in  a  row,  side  by  side,  would  extend  the  distance  of 
one  inch — and  I  do  not  even  know  what  gas  the 
mathematical  genius  who  made  the  computation  had 
in  mind.  The  same  authority  declared  that  if  the 
molecules  of  one  cubic  inch  of  gas,  at  ordinary  tem- 
perature and  pressure,  were  ranged  side  by  side  in  a 
row,  the  row  would  be  thirty-five  billion  miles  long. 
I  cannot  vouch  for  this;  I  never  counted  them. 
But  colloidal  particles  seem  to  be  aggregates  of  mole- 
cules and  yet  small  enough  to  be  shaken  around  by 
the  molecular  bombardment  they  receive.  We  may 
have  to  revise  our  ideas  about  the  size  of  molecules. 
Dr.  Irving  Langmuir,  of  Schenectady,  is  beginning  to 
develop  some  interesting  theories  in  regard  to  the 
shape  of  them.  But  colloidal  particles  seem  to  group 
themselves  together  by  means  of  their  free  energy, 
with  other  colloidal  particles  in  indefinite  propor- 

34 


PHASES   OF   MATTER 

tions,  and  thus  to  provide  for  an  infinite  variety  of 
such  associations.  At  least  this  seems  to  be  the  case. 
It  is  held  by  Jerome  Alexander,  who  is  an  authority 
on  colloid  chemistry.  But  there  are  those  who  regard 
it  as  unlikely.  The  study  of  colloid  chemistry,  which 
might  be  described  as  the  chemistry  of  uncrystallized 
matter  in  very  small  particles,  has  shed  a  great  deal 
of  light  upon  chemical  philosophy.  There  were  certain 
substances  which,  it  was  held,  would  not  combine  with 
one  another  except  in  solution.  Spring,  a  Belgian 
physicist,  discovered  that  if  they  were  ground  to  a 
fine  enough  powder  and  brought  together  dry  under 
heat  and  pressure,  they  would  combine.  As  Professor 
Bancroft  points  out,  in  very  fine  particles  we  have  a 
vastly  increased  surface  in  proportion  to  the  mass, 
and  that  is  where  chemical  energy  makes  its  attack. 
Another  interesting  fact  lately  brought  out  by  Dr. 
Colin  G.  Fink  is  that  electrical  conductivity  will 
follow  the  line  of  smallest  particles,  other  factors  be- 
ing unchanged,  and  thus  show  a  similarity  of  action 
between  chemical  energy  and  electrical  conductivity. 
The  philosophy  of  this  is,  the  smaller  the  particles 
the  closer  the  contact. 

The  jingle  which  follows  was  written  merely  to 
wheedle  a  little  amusement  out  of  colloid  chemistry. 
But  as  it  may  indicate  something  of  the  Brownian 
movements  of  colloidal  particles  to  those  who  have 
not  had  the  privilege  to  examine  them  through  the 
ultra-microscope,  I  shall  make  bold  to  print  it. 

THE   BROWNIAN   MOVEMENTS 

The  Brownian  movements  hold  their  sway 
And  grant  no  rest  the  livelong  day; 
They  also  rule  the  dance  all  night, 
As  you  may  see  by  proper  light, 
35 


EVERYMAN'S   CHEMISTRY 

The  particles  o'er  which  they  rule 
Are  like  young  maids  just  out  of  school, 
Or  like  some  youths — the  "dancing  men'  — 
Who  work  a  little  now  and  then, 
But  always  look  at  work  askance 
When  they  can  enter  in  a  dance. 
And  yet  these  girls  and  boys  are  poor, 
Short-winded,  listless,  slow,  and  dour 
Compared  with  particles  so  fine 
That  scorn  the  music  and  the  wine, 
And  whirl  and  jiggle,  up  and  down, 
And  right  and  left,  and  almost  drown, 
But  never  stop,  and  keep  it  up 
Within  the  beaker  or  the  cup, 
Or  on  the  microscope's  thin  slide; 
They  chasse*  every  way,  and  glide 
And  shake,  and  make  a  ladies'  chain, 
And  bow  and  back  away  again. 
And  when  you  think  they're  all  undone 
You'll  find  they've  only  just  begun. 
No  wonder  we  grow  weary  when 
We  watch  these  spots  beyond  our  ken, 
And  see  them  move  and  whirl  and  turn 
And  twist  and  wriggle,  skip  and  churn. 
It  makes  me  wild  to  see  them  go 
Without  a  destination;  so, 
While  watching  I'm  disposed  to  shout, 
"Jerome,  please  turn  that  arc-light  out." 
I've  sometimes  thought  this  Brownian  whirl 
Was  like  a  boy  or  like  a  girl, 
Or  rather,  if  we'd  seek  the  truth, 
We'd  find  its  simile  in  youth. 
But  youth,  as  I've  already  said, 
Is  too  inert,  too  slow,  too  dead, 
To  be  compared  with  this  untiring, 
Everlasting,  unperspiring, 
Rocking,  jerking,  bobbing  way 
Of  particles  by  night  and  day 
36 


PHASES   OF    MATTER 

That  stay  distraught,  yet  permanent, 

In  their  colloidal  tenement. 

And  so,  I  must  admit,  they  strike 

Me  as,  in  fact,  being  far  more  like 

A  very  aged  person  that 

Has  lost  his  teeth,  whose  gums  are  flat 

And  smooth,  who  works  his  jaw  all  day 

And  chews  his  senile  hours  away. 

But  similes  are  all  in  vain, 

And  so  we  are  brought  back  again 

Where  we  began:   these  movements  are 

Bewildering  and  singular. 

The  source  of  most  colloidal  fright 

Is  found  in  the  electrolyte. 

Its  advent,  though  it  be  disguised, 

Will  stop  the  dance.     They're  paralyzed, 

The  particles.     The  dance  will  stop 

And  down  the  particles  will  drop. 

Well,  we're  like  that.     Though  young  or  old, 

We  imitate  colloidal  gold. 

And  when  the  grim  electrolyte 

Grips  us  in  his  unconquered  might 

With  skull  and  cross-bones,  then  we  shout, 

As  we  fall  down:    "The  light  is  out." 


IV 

ELEMENTS   AND    THEIR   COMPOUNDS 

Faith  and  the  Dream-boy — The  Periodic  Law — Atomic  Weights — 
Elemental  Families — Elements  in  Life — The  Pons  Asinorum  of 
Chemistry — Chemical  Affinities — Baffling  Problems  of  Valence — 
Inert  Elements — Radicals — Acids  and  Bases — Difference  be- 
tween Compounds  and  their  Component  Parts — A  Man  in 
Solution — Catalysis — The  Chemical  Parson — The  Personality  of 
Matter— Carbon's  Ways 

ON  another  page  at  the  end  of  the  book  you  will 
find  a  list  of  the  elements  as  we  know  them  to-day. 
I  think  you  will  find  it  convenient  to  consult  the  list  as 
you  go  along.  I  doubt  if  it  is  a  permanent  list.  Ele- 
ments come  and  go  according  to  the  latest  findings  of 
one  man  of  research  after  another.  Among  the  metals, 
and  especially  among  those  found  in  the  rare  earths, 
they  are  very  tricky,  and,  to  tell  the  truth,  it  takes  more 
than  a  little  faith  to  believe  in  all  of  them.  As  ele- 
ments— that  is,  as  bodies  that  cannot  be  resolved  into 
simpler  substances  by  any  means  at  our  command — • 
they  should  be  permanent,  if  not  stable,  and  in  practice 
we  shall  do  well  to  call  them  so.  Our  business  is  with 
every-day  chemistry,  and  to  regard  the  whole  list  as 
elemental  is  the  best  thing  that  we  can  do. 

And  yet  the  dream-boy  will  beckon  us  on.  There  is 
the  Periodic  Law,  of  which  a  chemical  rhymester  once 
wrote : 

The  Periodic  Law 

Is  like  a  dogma  old; 
It  is  not  what  we  wish  it  were 
When  everything  is  told. 

38 


ELEMENTS    AND    COMPOUNDS 

Just  as  imperfectly  as  law  rhymes  with  were,  so 
imperfect  is  the  application  of  this  law  with  the 
knowledge  and  means  at  our  command.  But  let  us 
get  an  intimation  of  it  into  our  minds,  if  we  can.  It 
is  very  interesting.  The  atomic  weight  of  an  element 
is  based  on  its  relative  or  combining  weight.  For 
instance,  one  volume  of  oxygen,  weighing  sixteen 
ounces,  will  combine  with  twice  the  same  volume  of 
hydrogen,  which  weighs  only  two  ounces,  to  produce 
water.  Molecules  of  oxygen  and  hydrogen  contain 
two  atoms  each.  From  this  we  determine  that,  count- 
ing the  atomic  weight  of  hydrogen  as  one,  that  of 
oxygen  is  sixteen.  Now,  if  we  arrange  all  the  elements 
in  horizontal  rows  of  eight,  the  second  to  the  right  of 
the  first,  the  third  after  the  second,  and  so  on,  begin- 
ning with  the  lowest  atomic  weight  and  ending  with 
the  highest,  we  shall  have  a  table  of  the  elements, 
eight  wide,  like  a  company  of  soldiers  marching  in 
column  of  eight.  Then,  after  a  little  needful  rearrange- 
ment, we  note  a  remarkable  series  of  relationships, 
of  cousinships  we  might  say,  among  the  elements. 
It  is  not  those  that  stand  side  by  side  in  this  table 
that  have  similar  qualities ;  the  relation  between  them 
is  as  they  stand  in  vertical  rows,  above  and  below 
one  another.  As  we  counted  them  off,  in  the  hori- 
zontal rows,  they  show  no  special  relation  to  one 
another.  When  we  consider  each  as  part  of  a  vertical 
row,  on  the  other  hand,  we  find  that  the  elements 
of  these  groups  have  the  same  number  of  hooks  or 
affinities  to  combine  with  other  bodies;  their  combi- 
nations with  oxygen  are  of  a  similar  nature,  and,  with 
frequent  exceptions  and  many  differences,  they  have 
much  in  common.  We  shall  note  these  families  as 
we  proceed. 

With  some,  as  with  potassium  and  sodium  (potash 
4  39 


EVERYMAN'S    CHEMISTRY 

and  soda),  the  cousinship  is  so  evident  that  it  may  be 
seen  at  first  glance.  You  may  guess  the  relationship 
between  gold  and  silver,  but  when  it  comes  to  the 
similarities  of  oxygen  to  sulphur  you  may  prefer  to 
be  told,  and  even  then  not  believe  it  with  all  your 
heart  and  all  your  might.  And  yet,  because  of  this 
law,Mendeleeff  foretold  the  discovery  of  three  elements 
twenty-five  years  before  they  were  found,  and  he 
described  what  their  properties  would  be  and  what 
kinds  of  compounds  they  would  form.  There  is  a 
considerable  number  of  other  elements  that  may 
exist,  and,  if  they  do,  chemists  believe  that  they  know 
about  what  their  atomic  weights  will  be  and  something 
about  their  properties,  because  of  the  vacant  spaces 
in  this  table  of  the  Periodic  Law.  There  are  remark- 
able recurrent  qualities  that  display  themselves  in  this 
rhythm  of  the  elements,  but  these  things  have  been 
so  well  described  by  the  late  Robert  Kennedy  Duncan 
and  by  Geoffrey  Martin  in  their  books  that  I  shall  not 
try  to  repeat  them.  There  are  dreams  of  the  great 
rhythmic  swing  of  creation  in  the  thought  of  it;  but 
our  business  is  with  the  tangible  things  of  to-day 
and  the  working  hypotheses  about  them. 

In  other  words,  here  we  have  the  stuff  out  of  which 
everything  is  combined.  When  I  say  everything  I 
mean  it ;  the  content  of  every  nerve,  the  place  in  your 
brain  where  your  memories  are  stored  and  all  of  the 
earth  as  well  as  all  the  suns  and  stars.  The  brain 
after  death  is  a  different  thing  from  a  living  brain, 
but  there  is  no  reason  to  believe  that  either  during 
life  or  after  death  there  are  more  than  five  or  six 
elements  in  combination  in  it  at  any  time. 

Without  even  touching  on  the  mystery  of  life  and 
its  origin,  it  is  interesting  to  note  how  few  elements 
make  up  living  things.  It  is  also  interesting  to  ob- 

40 


ELEMENTS   AND   COMPOUNDS 

serve  how  few  elements  are  here  in  quantity  and  how 
many  of  them  exist  only  in  traces  on  the  earth.  The 
following  table,  prepared  by  Dr.  F.  W.  Clarke  in 
1916,  gives  the  average  distribution  of  the  elements 
in  earth,  air,  and  water  at  the  present  time.  In  con- 
nection with  this  table,  Dr.  Henry  Fairfield  Osborn 
calls  attention  to  the  fact  that  life  in  one  form  or 
another  has  taken  up  and  made  use  of  all  the  elements 
of  frequent  occurrence  except  aluminium,  barium,  and 
strontium,  which  are  extremely  rare  in  life  compounds, 
and  of  titanium,  which  thus  far  has  not  been  found 
in  any  living  cell.  These  can  be  introduced  into  arti- 
ficial organic  compounds,  and  it  is  a  fair  guess  that 
the  Missouri  clay-eaters  have  metabolized  some  alu- 
minium and  use  it  somewhere  in  their  bodies,  all 
unconsciously.  The  elements  which  enter  into  life 
forms  are  in  italics. 


Average, 
including 

Earth 

Water 

Air 

Atmosphere 

Oxygen  

47-17 

85-79 

20  .  8  (variable 

49-85 

to  some  extent) 

Silicon  

28.00 



26.03 

Aluminium  

7.84 

7-28 

Iron  

4-44 

4.12 

Calcium  

3-42 

•05 

3-18 

Magnesium  

2.27 

.14 

2.  II 

Sodium  

2-43 

I.I4 

2-33 

Potassium  

2.49 

.04 

2-33 

Hydrogen  
Titanium  

•23 
•44 

10.67 

variable 

•97 
.41 

Carbon  

•19 

.002 

variable 

•19 

Chlorine  

.06 

2.07 

.40 

Bromine 

008 

Phosphorus  

.  ii 

.10 

Sulphur  

.11 

.09 

.10 

Barium  

.09 



.09 

Manganese  

.08 

.08 

Strontium  

•°3 



•03 

Nitrogen  

78  .  o  (variable 

•  03 

to  some  extent) 

Fluorine  

.10 

.10 

All  other 

Elements 50 


.47 


EVERYMAN'S    CHEMISTRY 

Where  are  gold,  silver,  lead,  tin,  zinc,  and  the 
heavy  elements?  They  are  negligible  in  amount  com- 
pared to  the  lighter  ones.  Look  at  that  absurd  sili- 
con; in  combination  with  oxygen  it  is  sand,  and  as 
silicates  of  one  sort  or  another  it  constitutes  part  of 
most  rocks.  A  few  tons  are  reduced  (separated  from 
oxygen)  daily  at  Niagara  Falls,  and  this  metallic 
silicon  is  used  in  the  iron  industry  to  lure  the  oxygen 
away  from  iron  and  steel;  but  we  haven't  found  any 
other  general  use  for  it,  and  we  can't  eat  it.  In  com- 
bination with  oxygen  all  grains  use  it  to  form  a  sheath 
for  their  seeds,  but  its  part  in  life  is  very  slight  in 
comparison  with  much  rarer  elements.  Again,  in 
combination  with  oxygen  and  with  different  metals 
we  use  it  as  glass;  but  it  is  an  inert  thing  at  most 
times  and  seasons. 

This  mulling  over  elements  is  the  pons  asinorum 
of  chemistry.  Along  at  about  this  point  people  are 
likely  to  say:  " What's  the  use?  Chemistry  doesn't 
tell  us  anything  worth  knowing.  You  might  as  well 
say,  when  I  ask  you  what  sort  of  a  fellow  John  is, 
that  he  is  made  of  so  many  pounds  of  bone,  so  many 
pounds  of  flesh,  and  so  many  square  yards  of  skin. 
It  isn't  what  I  want  to  know  about  him  at  all." 
Then  they  drop  out  and  declare  that  they  have  looked 
into  chemistry,  and  that,  while  it  is  doubtless  a  useful 
study,  it  is  dull  and  uninteresting. 

This  would  be  true  if  we  stopped  right  here;  but 
we  must  remember  that  the  study  of  the  elements  is 
only  the  study  of  the  genealogy  of  things,  and  that 
is  not  the  end  of  chemistry  by  any  means.  Chemistry 
goes  on  to  study  things  after  they  have  been  pro- 
duced and  to  find  out  what  they  will  do.  That  is 
where  the  romance  comes  in.  It  is  in  combinations 
of  elements  that  they  are  interesting,  and  their  com- 

42 


ELEMENTS   AND    COMPOUNDS 


binations  are  up  to  more  tricks  and  have  more  ways 
of  their  own  than  the  stuff  that  they  are  made  of. 

Of  course  you've  heard  of  chemical  affinity  and  the 
time-worn  jokes  about  it.  The  subject  is  not  very 
clear,  and,  in  the  light  of  more  precise  research,  the 


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riflili 


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,,  |              i           •  ,  ,  ,                     '  ;     ', 

q 

rbon, 

EVERYMAN'S    CHEMISTRY 

will  in  the  light,  for  light  has  a  considerable  influence 
on  many  molecules  and  seems  to  start  the  atoms 
whirling  about  in  a  livelier  motion.  Many  will  not 
combine  dry,  but  will  in  solution.  The  most  frequent 
method  of  bringing  molecules  into  combination  is  by 
means  of  heat.  Heat,  as  we  know,  is  motion  among 
the  molecules,  and  with  heat  many  bodies  will  com- 
bine that  will  not  do  so  in  the  cold.  Then,  again,  if 
we  increase  the  heat  enough,  we  can  drive  the  con- 
stituent parts  of  a  body  out  of  combination,  some 
with  a  little  heat,  while  others  cling  together  so  tightly 
that  the  heat  of  the  interior  of  a  blast  furnace  will 
not  drive  them  apart.  And  again  there  is  catalysis, 
which  we  shall  take  up  later. 

Some  elements  have  no  affinity  at  all,  and  to  all 
appearances  will  combine  with  nothing.  These  are 
Sir  William  Ramsay's  inert  gases  of  the  air — argon, 
neon,  krypton,  xenon,  and  that  bewildering  helium, 
that  shows  up  so  unexpectedly  in  the  sun,  in  stars, 
in  certain  rocks,  and  in  meteorites  as  well  as  in  the 
air.  We  are  not  likely  to  refer  to  them  again.  Some 
elements  seem  inert,  and  it  appears  almost  impos- 
sible to  get  them  to  combine  with  other  elements, 
owing  to  the  tense,  unyielding  hold  the  atoms  have 
upon  one  another  in  the  molecule.  There's  nitrogen, 
for  instance,  a  gas  comprising  four-fifths  of  the  air. 
It  behaves  as  though  nothing  would  induce  it  to  com- 
bine with  anything,  and  yet,  once  it  is  brought  into 
combination,  it  seems  as  though  nothing  would  drive 
it  back  into  single  blessedness  again.  Most  explosives 
are  compounds  of  nitrogen,  and  when  the  blow-up 
takes  place  the  nitrogen  is  forced  out  of  combina- 
tion. Thereupon  it  usually  takes  up  with  some- 
thing else.  Nitrogen  is  the  liveliest  widower  of  all 
the  elements,  and  it  will  not  stay  single  if  there  is 

44 


ELEMENTS   AND    COMPOUNDS 

anything  else  to  combine  with  after  it  loses  its  mate. 
We  shall  discuss  some  of  its  ways  when  we  consider 
it  separately  later  on. 

Now  let  us  again  arrange  the  elements  in  a  row 
in  accordance  with  their  manifestations  in  the  scale 
of  affinity  for  one  another.  As  we  do  this,  it.  seems  as 
if  some  old  plutonic  parrot  of  John  Silver  were  con- 
stantly crying  out  the  refrain  from  below,  "  Pieces 
of  eight!  Pieces  of  eight!"  for  right  here  we  find  the 
shadow  of  the  Periodic  Law  before  our  eyes  once 
more.  What  is  not  shadowy  at  all  is  their  likes  and 
dislikes  for  one  another,  which  are  very  strongly 
marked. 

Then  we  have  combinations  of  elements  that  act 
very  like  the  elements  themselves — and  often  more  so, 
to  put  it  in  Irish.  They  are  the  radicals,  or  ions  of 
which  we  have  spoken,  and  are  composed  of  two  or 
more  atoms  with  .unsatisfied  affinities.  Again  there 
are  other  combinations  called  acids,  on  the  one  hand, 
and  bases  or  alkalies,  on  the  other;  and  these  range 
themselves  with  the  elements  in  the  row,  the  acids 
with  the  non-metals,  and  the  bases  with  the  metals. 
It  seems  as  though  there  were  a  distaff  and  a  spindle 
side  to  the  house — the  acids  combine  with  the  bases 
and  metals,  while  the  bases  combine  with  the  acids 
and  non-metals.  The  products  are  called  salts.  But 
I  think  it  will  only  lead  us  astray  to  attribute  the 
idea  of  sex  to  atoms  or  to  molecules  or  ions. 

What  is  an  acid  and  what  is  a  base?  An  acid  has  a 
sour  taste,  and  is  the  opposite  of  a  base — but  what 
does  that  mean?  We  have  seen  how  the  acids  range 
themselves  along  the  scale  of  affinity  of  the  elements, 
on  the  non-metal  side;  so  the  charge  is  electro-nega- 
tive. It  is  not  an  acid  save  in  the  presence  of  water. 
This  is  another  statement  that  is  better  taken  on 

45 


EVERYMAN'S    CHEMISTRY 

faith  than  tested  out.  There  always  is  some  water 
around,  in  the  air  and  everywhere,  so  it  is  just  as 
well  not  to  toy  with  100  per  cent,  sulphuric  acid,  on 
the  ground  that  it  will  be  inactive.  There  is  always 
one  or  more  hydrogen  atoms  in  the  molecule  of  an  acid, 
and  these  hydrogen  atoms  are  one  business  end  of  the 
molecule,  and  the  rest  of  it  is  the  other. 

I  have  been  urged  to  elaborate  the  theory  of  acids 
and  bases  to  make  the  conception  of  them  more 
clear.  Let  us  put  down  the  acids  as  electro-negative, 
and  the  bases  as  electro-positive.  An  acid  must  have 
water  present,  and  so  must  a  base.  An  acid  will 
often  attack  a  metal,  but  water  must  be  present  in 
the  air  or  on  hand  to  form  the  metallic  hydroxide,  the 
combination  with  the  OH  radical.  The  acid  gives  up 
H  (hydrogen)  ions,  and  the  base  gives  up  -OH  ions, 
and  the  result  is  a  salt  composed  of  the  acid  less  its 
hydrogen  ions  combined  with  the  base  less  its  -OH 
ions.  And  besides  the  salt  we  have 

H    +    OH    =    H2o 

hydro-        oxy-  water 

gen      hydrogen 


But  some  acids  and  bases  are  very  strong,  while 
others  are  very  weak.  Why  is  this  ?  The  same  hydro- 
gen will  produce  weak  H  ions  in  one  acid,  and  very 
powerful  or  highly  charged  H  ions  in  another.  The 
same  holds  true  with  bases.  You  may  recall  that  we 
said  the  ions  were  always  in  equilibrium,  that  they 
were  balanced,  and  that  for  every  positively  charged 
one  there  was  a  negatively  charged  mate.  Very 
well,  then,  if  this  affinity  for  one  another  is  very 
great,  the  acid  or  base  is  strong;  if  it  is  slight,  it  is 
weak.  Let  us  take  sulphuric  acid,  H2SO4,  again, 

46 


ELEMENTS    AND    COMPOUNDS 

because  we  are  familiar  with  it.  It  contains  two  H 
ions  and  one  SO4  ion.  Their  affinity  is  great,  and  the 
acid  is  strong.  The  hydrogen  and  SO4  ions  are  sepa- 
rated in  the  solution,  but  balanced  by  a  great  affinity. 
Now  let  us  bring  that  SO4  ion  within  the  sphere  of 
influence  of  the  salt  of  a  weak  acid,  say  carbonate  of 
soda,  or  soda  ash,  Na2CO3.  Let  us  bring  the  Na  ions 
of  the  carbonate  of  soda  in  between  the  SO4  ions 
and  the  H  ions  with  which  it  is  paired  in  balance. 
What  chance  has  that  poor  CO3  ion  of  carbonic  acid, 
H2CO3,  which  is  not  even  known  in  a  free  state?  It 
has  no  chance  at  all.  Right  away  the  sodium  ion, 
Na,  is  grabbed  by  the  SO4  ions,  and  we  have  sodium 
sulphate,  or  Na2SO4.  That  is  a  salt.  Those  two 
H  ions  of  each  sulphuric  acid  molecule  find  a  weak 
CO3  ion  which  is  being  turned  adrift.  They  take  up 
one  atom  of  oxygen  to  produce  water,  H2O,  and 
leave  CO2  instead  of  CO3.  CO2  is  carbon  dioxide, 
the  so-called  carbonic-acid  gas  which  escapes  into 
the  air. 

There  are  some  acids  that  need  water  as  much  as 
others  do  for  their  reactions,  but  they  do  not  keep 
it  in  their  molecules  in  a  free  state.  Muriatic  or  hydro- 
chloric acid,  HC1,  is  a  gas  very  soluble  in  water.  The 
true  acid  should  be  H3C1O,  because  HC1  +  H2O  = 
H3C1O.  But  only  one  H  atom  becomes  ionized,  not 
the  three.  Therefore  hydrochloric  acid  is  written 
just  HC1,  and  it  is  one  of  the  strongest  acids  known. 

A  base  does  business  on  the  metal  side.  It  may  be 
a  metal  or  it  may  have  an  oxygen  atom  with  a  hydro- 
gen atom  attached,  an  -O-H  ion,  as  it  is  called.  That 
hyphen  on  the  left  of  the  O  (for  oxygen)  indicates 
that  one  of  its  affinities  is  free  and  the  other  (for 
oxygen  is  bi-valent)  is  engaged  with  the  one  hook  of 
the  hydrogen  atom.  Now  let  us  bring  an  acid  and  a 

47 


EVERYMAN'S   CHEMISTRY 

base  together  and  see  what  happens,  taking  sulphuric 
acid  and  caustic  soda. 


H2SO4     +     2NaOH     =     Na2SO4     +     2H2O 
sulphuric  caustic  sodium  water 

acid  soda  sulphate 

Do  you  see  what  happened?  The  two  hydrogen 
ions  of  each  molecule  of  sulphuric  acid  and  the  OH 
ions  of  the  two  molecules  of  the  caustic  soda  combined 
to  make  two  molecules  of  water,  while  the  sulphur 
ion  of  each  acid  molecule  combined  with  the  sodian 
ions  of  both  the  caustic  soda  molecules  to  produce 
a  salt,  the  sulphate  of  sodium.  So  an  acid  and  a  base 
combine  to  form  a  salt,  with  water  on  the  side.  A 
simple  test  is  with  the  well-known  litmus  paper,  a 
vegetable  dyestufE  with  which  unsized  paper  is  colored. 
Acid  turns  it  red  and  an  alkali  or  base  turns  it  blue. 
All  bodies  are  not  either  acids,  bases,  or  salts.  A 
great  many  are,  but  not  all.  And  you  observe  that 
the  frequent  allusions  to  acids  and  bases  as  male 
and  female  are  not  altogether  happy;  they  do  not 
reproduce  their  kind;  there  is  no  happy  progeny  of 
little  acids  and  bases  as  the  result  of  their  combination. 
They  produce  salts  and  water.  Chemistry  is  full  of 
romance,  but  this  is  not  the  place  to  find  it.  Some 
acids  are  not  known  in  their  acid  state ;  they  are  known 
as  anhydrids — that  is,  the  body  which  with  water 
produces  the  acid — and  they  are  also  known  in  their 
salts.  We  often  speak  of  carbonic-acid  gas,  which 
is  carbon  dioxide,  or  CO2.  It  is  not  an  acid;  it  is  the 
anhydrid  of  an  acid,  and  the  acid  is 

CO2  +  H2O  =  H2CO3, 
carbon  water  carbonic 
dioxide  acid 

48 


ELEMENTS    AND    COMPOUNDS 

which  nobody  has  been  able  to  produce  in  an  isolated 
state.  But  the  salts  of  this  acid  are  among  the  most 
widely  known.  For  instance,  soda  ash,  as  it  is  called, 
is  the  carbonate  Na2CO3,  of  which  millions  of  tons 
are  produced.  So  the  best  guess  is  that  it  forms,  but 
is  too  impermanent,  water  being,  let  us  say,  better 
content  to  be  H2O,  and  carbon  dioxide  to  be  CO2 
than  to  mate  up  as  real  carbonic  acid  except  for  a 
long  enough  fraction  of  an  instant  to  conform  to  the 
theory — or,  to  use  a  biblical  expression,  "that  the 
prophecy  might  be  fulfilled." 

Chemical  compounds  have  very  little  in  common 
with  the  elements  which  compose  them.  As  I  said 
before,  the  elements  are  the  genealogical  part  of  the 
study,  and  genealogy  is  interesting  enough  until  you 
begin  to  bore  people  with  it,  and  then  we  must  not 
blame  them  if  they  run  away. 

I  would  like  to  remind  you  of  a  few  well-known 
bodies,  and  point  out  how  vastly  they  differ  from  the 
elements  that  compose  them. 

There  is  sulphuric  acid,  or  oil  of  vitriol,  for  instance. 
It  is  a  combination  of  sulphur,  oxygen,  and  hydrogen. 
Nitric  acid,  composed  of  the  three  gaseous  elements, 
nitrogen,  oxygen,  and  hydrogen,  is  another  ruthless 
agent  of  destruction.  It  used  to  be  transported  in 
carboys,  which  are  great  glass  bottles  packed  with 
straw  in  wooden  boxes.  As  soon  as  a  bottle  breaks, 
up  go  the  straw  and  the  wood  in  flames.  Now,  when 
possible,  it  is  transported  mixed  with  strong  sulphuric 
acid,  which  may  be  carried  in  iron  tank-cars  for  rea- 
sons which  will  be  given  in  the  chapter  on  sulphuric 
acid. 

Dr.  Geoffrey  Martin  tells  of  a  laborer  in  one  of  the 
great  German  chemical  works  who  fell  into  a  large 
vat  filled  with  mixed  sulphuric  and  nitric  acids. 

49 


EVERYMAN'S    CHEMISTRY 

Some  one  heard  him  utter  a  shout,  but  no  one  saw 
him.  And  nobody  found  him.  There  was  no  sign 
of  him  to  be  discovered,  or  of  his  hair,  his  hat,  his 
boots,  or  his  clothes,  or  his  buttons,  or  the  ladle 
he  was  supposed  to  be  carrying.  He  simply  was  not. 
The  widow  wanted  her  life  insurance,  but  the  adjuster 
developed  the  theory  that  he  had  gone  to  America. 
Yet  all  opportunity  for  egress  from  the  works  was 
carefully  watched,  and  the  records  showed  that  he 
was  still  there.  His  presence  in  the  vat  was  proved 
by  the  percentage  of  phosphorus  which,  as  a  normal 
man,  he  was  supposed  to  add  to  it,  and  which,  without 
a  man  in  solution,  would  not  be  present.  That  was 
the  proof  of  loss. 

Alkalies  are  just  as  insatiate.  Caustic  soda,  caustic 
potash,  caustic  lime,  combinations  of  oxygen  and  hy- 
drogen with  the  metals  sodium,  potassium,  and  cal- 
cium are  powerful  alkalies,  and  will  drive  out  any 
frailer  bases  there  may  be  within  reach  and  combine 
with  their  acid  partners.  Fats  are  split  as  with  a 
cleaver  with  soda,  the  base  combining  with  the  fatty 
acids  to  produce  soap,  and  the  mild  and  emollient 
glycerin  is  set  free.  Glycerin  is  mildly  basic  in  its 
nature,  but  it  has  no  chance  with  caustic  soda 
around. 

A  very  interesting  subject  in  the  study  of  chemistry 
is  called  catalysis,  and,  to  my  way  of  thinking,  it  does 
more  to  indicate  the  whimsical  nature  of  things  in- 
animate, what  might  be  called  the  personality  of 
matter,  than  anything  else.  Let  us  take  two  bodies 
that,  according  to  all  the  rules  and  all  our  reasoning, 
should  combine  when  we  bring  them  together.  They 
should,  but  they  do  not.  Of  course,  there  is  a  reason 
for  this,  but  what  we  are  after  is  the  reaction.  If 
you  strike  a  match,  the  reaction  will  begin  from  the 


ELEMENTS    AND    COMPOUNDS 

heat  of  the  rubbing.  Hold  the  match  to  the  prepared 
surface  and  nothing  will  happen.  Heat  makes  the 
atoms  move  around  in  the  molecule  at  a  livelier  pace. 
They  seem  to  swing  in  a  larger  orbit  and  are  more 
easily  caught  up  by  some  other  matable  atom  that 
is  swinging  around  in  its  molecule.  But  in  these  cases 
nothing  happens.  We  have,  let  us  say,  two  bodies 
which  should  combine,  but  don't,  dissolved  in  water 
in  one  vessel.  We  heat  it  and  shake  it,  and  still 
nothing  happens.  Then  we  add  the  catalyst,  which 
is  a  foreign  body,  and  to  all  appearances  it  has  no 
relation  to  what  we  have  or  the  combination  we  want ; 
nevertheless,  as  soon  as  it  is  added,  sometimes  even 
in  an  absurdly  slight  amount,  presto!  the  solution 
straightway  froths  up,  there  is  a  grand  commotion, 
and  a  reaction  involving  every  molecule  in  the  solution 
takes  place.  What  we  wanted  to  happen  does  happen. 
And  the  little  catalyst  may  be  found  at  the  bottom  of 
the  beaker  just  as  it  was  when  we  put  it  in,  to  all 
appearances,  chemical  and  otherwise,  unchanged. 

There  are  volumes  and  volumes  written  about  this, 
and  there  are  theories  galore,  but  I  shall  not  develop 
them.  The  fact  is,  the  catalyst,  which  is  the  active 
agent  in  the  process  of  catalysis,  behaves  generally 
like  a  human  trouble-maker.  The  process  comes  fre- 
quently into  play  in  the  industries,  and  by  means  of  it 
the  Germans  have  been  able  to  carry  on  the  war — 
as  you  shall  presently  see. 

Then  there  is  the  very  opposite,  in  which  such  a 
body  can  retard  or  hinder  a  reaction  that  otherwise 
would  take  place.  This  is  also  very  like  some  kill- 
joys, who,  by  their  mere  entrance  into  a  room,  par- 
alyze the  energy  of  every  one  else,  suffuse  it  with 
silence,  and  spread  inertia.  We  can  find  the  personal 
qualities  of  nearly  every  one  we  know  in  the  great 


EVERYMAN'S    CHEMISTRY 

domain  of  inanimate  things  in  chemistry.  Matter 
is  whimsical ! 

We  have  one  other  subject  to  consider  before  we 
go  into  detail  in  this  book,  and  that  is  the  compounds 
of  carbon.  Carbon  differs  from  nearly  all  other  ele- 
ments in  that  one  atom  of  carbon,  with  its  four  hooks 
or  bonds,  will  use  up  one  or  more  of  them  with  one 
or  more  other  elements  or  radicals  and  attach  all 
that  are  left  over  to  another  carbon  atom.  Other 
elements,  except  silicon,  do  not  seem  to  care  for  this 
sort  of  thing,  although  it  does  occur,  occasionally. 
Oxygen  is  sometimes  given  to  the  practice,  but  oxygen 
has  only  two  bonds,  and  it  is,  anyway,  much  more 
conservative  in  this  respect.  Carbon  atoms  hook  on 
to  other  carbon  atoms,  with  hydrogen  and  oxygen 
and  nitrogen  and  all  sorts  of  other  elements  and 
radicals  on  the  side,  but  chiefly  with  the  three  I  have 
mentioned.  Next  in  order  come  the  halogens,  then 
sulphur  and  phosphorus. 

Carbon  compounds,  of  which  there  are  more  than 
all  others  put  together,  are  called  organic  because 
everything  that  has  life  as  we  understand  it  (which, 
for  instance,  is  composed  of  cells)  contains  carbon. 
The  name  was  given  long  ago  when  it  was  thought  im- 
possible to  produce  in  the  laboratory  any  of  the 
products  of  life.  The  name  sticks,  and  it  is  not  such 
a  bad  one,  after  all.  For  all  the  carbon  we  know  has 
had  a  history  of  life  at  one  time  or  another,  and  if  it 
takes  a  stretch  of  the  imagination  to  refer  to  asphalt 
and  soap  as  things  having  or  having  had  life,  it  is 
well  that  this  should  be  so.  We  may  as  well  get 
used  to  stretching.  When  we  consider  the  names 
of  wrath  that  many  organic  compounds  bear,  the 
endurance  is  submitted  to  a  greater  strain. 

Carbon  has  two  general  schemes  of  combination. 

52 


ELEMENTS   AND    COMPOUNDS 

First  it  combines  in  strings  or  chains  of  one  carbon 
atom  attached  to  another,  a  third  attached  to  the 
second,  a  fourth  to  the  third,  and  so  on,  as  far  as 
you  want  to  go,  with  all  sorts  of  developments  at- 
tached to  the  free  affinities  on  the  sides.  The  other 
system  is  known  as  the  aromatic  or  benzol  group  of 
organic  compounds,  and  in  these  six  carbon  atoms  ar- 
range themselves  in  a  hexagon,  or  "benzol  ring," 
as  it  is  called,  and  each  carbon  atom  has  at  least  one 
affinity  free.  Then  these  hexagonal  benzol  rings 
mate  up  with  one  another  and  appear  as  twin  rings, 
as  in  naphthalene,  or  triplet  rings,  as  in  anthracene, 
and  at  each  point,  where  there  is  a  free  affinity  or 
where  an  atom  or  radical  with  a  lighter  grip  can  be 
substituted  for  one  with  a  stronger  one,  another  chain, 
or  another  radical,  or  another  element  may  be  added. 
So  the  number  of  combinations  is  bewildering.  We 
shall  consider  some  of  these  later  on. 


CHEMICAL   NAMES   AND   PHRASES 

How  They  Are  Used — Terminations  in  ict  ous,  ide,  ate,  and  tie — 
The  Convenience  of  Chemical  Language — An  Attempt  to  Explain 
Its  Ugliness 

THE  chemical  names  of  substances  are  indeed 
words  of  confusion  to  the  uninitiated.  And  yet 
they  are  useful  beyond  measure.  Of  course  every 
substance  must  have  a  name,  else  it  could  not  be 
catalogued,  and  we  should  be  unable  to  distinguish  it. 
It  would  not  do  to  name  them  in  terms  of  endearment 
and  romance,  like  Pullman  sleeping-cars — there  are 
not  enough  names  to  go  round,  and  that  method  would 
be  more  confusing  still.  What  the  chemical  name 
tries  to  do  is  to  tell  what  a  thing  is  made  of;  it  tries 
to  describe  the  molecules,  and  it  succeeds  fairly  well. 
The  elements  are  referred  to  by  their  names.  I 
do  not  want  to  try  your  patience,  but  again  I  commend 
to  you  the  table  of  elements  at  the  back  of  the  book. 
And  yet  only  a  few  of  them  are  often  met  with.  Most 
of  them  are  rare.  Compounds  of  two  elements  end 
in  ide.  Thus  common  salt  (NaCl)  is  chloride  of 
sodium;  iodide  of  potash  is  KI;  PbS  is  sulphide  of 
lead;  A12S3  is  aluminium  sulphide,  etc.  Compounds 
of  one  element  with  oxygen  are  called  oxides,  and  if 
there  are  several  different  oxides  of  the  same  element, 
the  Greek  or  Latin  prefix  is  used.  Thus  S02  is  sulphur 

54 


CHEMICAL   NAMES    AND    PHRASES 

dioxide;  S03  is  sulphur  trioxide.  With  carbon,  CO 
is  carbon  monoxide;  CO2  is  carbon  dioxide,  etc. 
Sometimes  there  is  more  than  one  oxide,  and  the  rela- 
tion of  the  other  element  is  complex,  as,  for  instance, 
in  the  case  of  iron,  of  which  FeO  is  ferrous  oxide,  and 
Fe2O3  is  ferric  oxide,  because  the  termination  ic  means 
more  oxygen  in  the  molecule  in  proportion  to  the 
other  element  than  ous.  The  termination  ic  also 
indicates  the  engagement  of  a  larger  number  of  bonds 
of  an  element  than  ous.  The  Latin  expression  for 
iron  is  used  because  you  can't  make  an  adjective 
very  well  out  of  iron  without  the  use  of  ironic,  which 
is  already  pre-empted  by  literature. 

Again,  FeCl2  is  ferrous  chloride,  while  FeCl3  is 
ferric  chloride.  There  are  more  hooks  engaged — the 
valency  is  greater  in  the  ic  compounds  than  in  those 
ending  in  ous. 

With  acids,  the  termination  ic  is  the  usual  one,  the 
one  in  greatest  use  or  the  one  first  discovered,  as 
sulphuric,  hydrochloric,  or  oxalic  acids.  If  there  is  a 
second  acid  like  the  first,  but  containing  less  oxygen, 
the  term  ous  is  used.  For  instance,  the  anhydrid  of 
sulphuric  acid  is  SO3,  which  in  effect  is  sulphuric 
oxide,  although  it  is  usually  called  "S-O-three,"  or 
sulphur  trioxide.  Add  water  (H2O)  to  SO3,  and  we 
have  H2SO4,  which  is  sulphur^  acid.  SO2  is  the 
product  of  sulphur  when  burned.  It  is  sulphurous 
oxide  because  it  contains  less  oxygen  than  sulphuric 
oxide.  It  is  also  called  S-O2  and  sulphur  dioxide. 
Now  add  water  to  it  and  we  have  the  acid  SO2  + 
H2O  =  H2SO3,  or  sulphurous  acid.  So  acids  ending 
in  ous  have  less  oxygen  in  the  molecule  in  proportion 
to  other  atoms  than  acids  ending  in  ic.  But  sometimes 
there  are  more  than  two  acids.  Then  the  one  contain- 
ing most  oxygen  has  the  prefix  per  and  the  suffix  ic, 
5  55 


EVERYMAN'S    CHEMISTRY 

while  the  one  having  the  least  is  hypo ous.    For 

instance : 

HC1O4  is  perchloric  acid.  KC1O4  is  potassium  perchlorate. 

HC1O3  is  chloric  acid.  KC1O3  is  potassium  chlorate. 

HClOa  is  chlorous  acid.  KC1O2  is  potassium  chlorite. 

HC1O  is  hypochlorous  acid.  KC1O  is  potassium  hypochlorite. 

Per  indicates  beyond,  above,  and  so  over,  while 
hypo  means  under  or  less.  Acids  with  names  ending 
in  ic  make  salts  ending  in  ate;  those  ending  in  ous 
make  salts  ending  in  ite. 

Sesqui  means  one-half  more,  so  that  oxides  like 
alumina,  A1203;  ferric  oxide  Fe2O3,  etc.,  which  appear 
to  contain  half  as  much  again  of  oxygen  as  of  the  other 
element,  are  sometimes  referred  to  as  sesquioxides. 

The  language  is  not  hard  to  pick  up  if  one  only  has 
occasion  to  use  it.  It  is  awkward  and  unconscionably 
ugly,  but  it  tells  the  story  better  than  any  other 
medium  that  is  known.  And  it  is  the  same  in  all 
languages.  We  shall  consider  the  names  in  organic 
chemistry  when  we  get  to  them. 

It  is  really  too  bad  that  the  language  of  chemistry 
is  so  ugly.  I  venture  the  belief  that  it  is  the  lack  of  art 
in  the  speech  of  science  that  drives  people  away  from 
considering  it.  Science  has  not  been  much  taught 
except  for  the  last  fifty  or  seventy-five  years,  and 
ideas  have  come  faster  than  good  expressions  have 
been  found  for  them,  so  that  science  and  its  language 
is  very  like  Coal  Oil  Johnny  with  his  sudden  wealth. 
It  has  not  learned  as  yet  that  grace  and  ease  of  expres- 
sion that  distinguish  the  Humanities.  Words  like 
"polymerization"  and  "specificity"  are  really  too 
awkward  for  general  use,  and  yet  so  great  has  been 
the  need  for  expression  to  describe  the  increasing  num- 
ber of  scientific  ideas  that  we  have  had  to  be  thankful 
for  any  old  vocal  noise  that  would  indicate  them. 

56 


PART   SECOND 
INORGANIC   CHEMISTRY 


VI 

AIR   AND   WATER 

Oxygen — Its  Ubiquity  and  Avariciousness — The  Mystery  of  Sleep — 
Fire — Ozone — Oxidation  and  Reduction — Disinfection — Air — 
Effects  of  Heat — Freezing-Machines — Doctor  CottrelTs  Inven- 
tion and  His  Use  of  It — The  Unutilized  Power  of  Air  Currents — 
Hydrogen — Water — Why  it  Rains — What  is  Man? — He  is  Twelve 
Pounds  of  Ashes  and  Eight  Buckets  of  Water — Why  it  is  not 
nearly  always  winter — Combinations  with  Water — Hard  and 
Soft  Water — How  to  Soften  it — Lime-soda  Process — Permutit — 
Making  Water  Wholesome. 

"r"FHE  heathen  in  his  blindness  bows  down  to 
A  wood  and  stone,"  but  if  he  had  studied  chem- 
istry he  surely  would  have  worshiped  oxygen.  We 
can  imagine  him  engaging  in  genuflections  before  an 
effigy  with  wings  to  indicate  the  air,  and  the  tail  of 
a  fish  to  show  forth  water,  and  with  as  many  other 
attributes  as  the  devout  sculptor  could  affix  to  it. 

Oxygen  gives  us  life — in  so  far  as  we  cannot  live 
without  it  for  more  than  a  very  few  minutes.  It  is 
the  most  ubiquitous  of  the  elements. _  One-half  of 
the  crust  of  the  earth  is  oxygen,  so  is  one-fifth  of  the 
air,  and  so  is  one- third  by  volume,  but  not  by  weight, 
of  water.  We  breathe  it  in  in  a  free  state,  and  exhale, 
in  the  place  of  some  of  it,  carbonic-acid  gas,  or  carbon 
dioxide,  as  it  is  more  properly  called.  You  can  prove 
this  by  buying  a  little  lime-water,  pouring  it  into  a 
glass,  and  blowing  through  a  pipe-stem  or  a  straw 

59 


EVERYMAN'S    CHEMISTRY 

into  the  lime-water.  An  insoluble,  white  precipitate 
is  immediately  formed  which  is  carbonate  of  lime. 
The  carbonic-acid  gas  which  you  blow  out,  and  which 
is  mildly  acid  with  water,  combines  with  the  lime, 
which  is  a  strong  alkali,  to  form  this  carbonate.  Now 
marble  is  carbonate  of  lime,  so  that  with  lime-water 
enough  and  wind  enough,  and  the  needful  procedure 
in  fusing  afterward,  one  might  produce  his  grave- 
stone out  of  his  own  proper  person.  It  would  give 
an  aspirant  a  chance  for  "a  place  in  the  world  in  the 
eyes  of  men"  after  he  had  passed  away,  an  opportu- 
nity to  be  both  cremated  and  preserved. 

It  appears,  from  researches  made  in  physiological 
laboratories,  that  oxygen  plays  a  very  important  part 
in  what  we  call  the  mystery  of  sleep.  Although  we 
continue  both  asleep  and  awake  to  inhale  the  free 
oxygen  and  to  exhale  oxygen  that  has  done  its  work 
of  oxidation  and  is  in  combination  with  carbon  as 
carbon  dioxide,  there  is  a  difference  in  the  compara- 
tive amounts  of  oxygen  inhaled  and  exhaled  at  such 
times.  While  we  are  awake  it  seems  we  exhale  more 
oxygen  than  we  inhale.  When  we  sleep  we  inhale 
more  than  we  exhale.  We  deplete  the  store  awake  and 
increase  it  while  we  sleep.  Now  we  cannot  live  with- 
out it.  It  provides  by  its  reactions,  by  processes  of 
oxidation  within  us,  for  bodily  heat  and  for  the 
chemical  processes  of  life.  How  needful  it  is  we  are 
reminded  when  we  consider  how  quickly  we  are 
drowned. 

In  the  history  of  torture  one  of  the  most  cruel 
methods  of  putting  culprits  to  death  was  simply  to 
keep  them  awake  until  they  died.  Without  sleep  they 
could  not  make  up  for  the  oxygen  lost  and  so  they 
died  of  oxygen  starvation.  It  is  said  that  there  is  no 
record  of  the  ability  of  executioners  to  keep  any  one 

60 


AIR   AND   WATER 

awake  over  five  days.  I  make  this  statement  from 
memory  only. 

Plants  breathe  in  carbon  dioxide  and  breathe  out 
oxygen.  In  much  less  measure,  some  of  them  do  the 
opposite. 

Oxygen  combines  with  metals  to  make  oxides. 
Many  metals  are  found  in  this  form.  The  fires  that 
we  see  are  chiefly  carbon  and  hydrogen  combining 
with  oxygen  at  such  a  rate  that  the  combining  par- 
ticles grow  white  hot  and  give  light.  Oxygen  dissolves 
slightly  in  water,  and  fish  get  most  of  what  they 
need  that  way.  It  is  in  rocks  and  in  sand  and  in  all 
living  things.  The  reason  why  our  bodies  are  main- 
tained at  blood  heat  is  because  of  the  oxygen  that  is 
going  into  combination  within  them.  We  are  slowly 
burning  so  long  as  we  live.  If  we  inhale  air  that  con- 
tains much  more  than  one-fifth  part  oxygen,  it  makes 
us  hilarious — drunk,  in  fact.  The  great  melodrama 
in  which  the  dashing  speculator  leads  oxygen  into  the 
air-ducts  of  the  stock-exchange  and  so  excites  the 
traders  that  stocks  go  up  and  he  makes  his  fortune 
has  not  been  written  yet,  but  here  is  the  chance.  I 
claim  no  copyright  on  the  idea. 

The  oxygen  atom  has  two  hooks,  and  there  are  two 
atoms  in  the  molecule,  except  when  a  current  of  elec- 
tricity short-circuits  or  jumps,  as  from  one  cloud  to 
another,  and  thus  produces  lightning,  and  then  a  little 
ozone  is  formed.  Ozone  is  oxygen,  but  with  three 
atoms  in  the  molecule  instead  of  two,  the  atoms  con- 
nected up,  as  in  the  corners  of  a  triangle,  with  one 
arm  or  hook  engaged  on  either  side.  It  is  not  stable; 
the  one  extra  atom  soon  disengages  itself,  and  then 
it  is  ready  for  business  to  oxidize  things. 

Getting  one  or  more  atoms  of  oxygen  into  a  combi- 
nation is  called  oxidation.  Getting  atoms  of  oxygen 

61 


EVERYMAN'S   QHEMISTRY 

out  of  a  molecule  is  called  reduction.  Ozone,  there- 
fore, is  an  oxidizing  agent.  On  the  other  hand,  small 
particles  of  iron,  heated,  will  take  up  oxygen  from 
many  compounds,  and  that  makes  it  a  reducing 
agent.  A  smelter,  that  melts  up  ores  and  separates 
the  free  metals  from  their  oxides,  is  a  reduction  works. 
If  we  imagine  the  earth  as  without  form  and  void, 
we  might  as  well  imagine  that  there  was  much  more 
oxygen  in  a  free  and  uncombined  state  than  now, 
until  all  the  silicon  and  the  metals  were  oxidized; 
but  that  they  are  now  in  an  approximate  state  of 
equilibrium,  animals  and  fires  taking  it  up  and  plants 
giving  it  back  to  the  air  again.  To  produce  oxygen 
for  the  industries,  free  from  nitrogen,  two  methods 
are  most  frequently  used.  One  is  the  electrolysis  of 
water,  whereby  one  volume  of  oxygen  collects  in  a 
vessel  over  one  pole  and  two  of  hydrogen  over  the 
other.  The  other  method  is  by  liquefying  air  and  dis- 
tilling off  the  nitrogen. 

The  way  to  determine  whether  oxygen  is  present 
in  excess  in  a  container  or  a  stream  of  escaping  gas 
is  to  light  a  splinter  of  wood  or  a  straw,  blow  out  the 
flame  while  leaving  a  spark,  and  then  hold  the  end 
with  the  spark  so  that  it  will  serve  as  a  test.  If  oxy- 
gen is  present  in  excess  the  spark  will  burst  into 
flame.  A  jet  of  burning  oxygen  and  hydrogen,  called 
the  oxy-hydrogen  flame,  or,  better  still,  oxygen  and 
acetylene  gas,  known  as  the  oxy-acetylene  flame,  will 
make  a  flame  so  hot  that  it  is  used  for  cutting  iron 
and  steel  through  almost  any  thickness. 

Oxygen  is  one  of  the  great  disinfectants.  If  brought 
into  contact  with  the  bacilli  of  disease  it  will  usually 
oxidize  them  and  render  them  harmless.  If  atmos- 
pheric air  is  pumped  into  sewage  as  it  comes  from 
city  sewers,  it  will  cause  all  the  insoluble  organic 

62 


AIR   AND    WATER 

matter  to  precipitate  in  the  form  of  stable  bodies,  at 
once  harmless  and  approximately  inoffensive,  and  of 
enormous  value  as  fertilizer.  This  is  the  line  of  re- 
search for  the  economic  'and  harmless  disposal  of 
sewage. 

The  nature  of  four-fifths  of  the  air  we  shall  have  to 
postpone  until  we  come  to  nitrogen;  but  some  of  the 
physical  properties  of  air  we  may  consider  at  this 
point.  It  presses  in  upon  us  at  about  the  rate  of 
fifteen  pounds  to  the  square  inch.  We  live  on  the 
oxygen,  which  is  about  one-fifth  of  it.  According  to 
its  content  of  water,  carbon  dioxide,  dust,  spores  of 
life,  a  slight  divergence  in  the  ratio  of  oxygen  to  the 
whole,  and  smoke  or  fumes  of  one  sort  or  another,  it 
is  pleasant  or  unpleasant,  wholesome  or  unwholesome. 
The  amount  of  dust  that  it  carries  is  considerable; 
indeed,  it  is  the  minute  particles  of  dust  that  diffuse 
the  light  and  that  may  have  a  marked  effect  upon 
rainfall.  If  a  beam  of  light  strikes  through  a  dark 
room,  we  get  an  idea  of  the  amount  of  dust  there  is 
floating  around.  We  can  see  it  then.  Air  is  not  a 
carrier  of  electricity,  but  the  electricity  breaks  through 
at  times  under  pressure,  as  we  see  in  lightning.  Moist 
air  is  more  of  a  conductor  than  dry  air;  that  is, 
electricity  breaks  through  moist  air  more  easily  than 
through  dry  air.  Now  pure  water  is  not.  a  conductor, 
but  even  the  water  up  in  the  sky  is  not  absolutely 
pure.  Hardly  anything  in  nature  is  pure;  nature  is 
the  most  omnivorous  mixer  there  is.  Like  all  other 
gases,  whether  chemically  pure  or  mixed,  air  grows 
hot  as  we  compress  it  and  cools  as  it  expands. 

You  may  remember  some  pages  back  how  gases 
contract  as  the  temperature  falls  and  expand  as  they 
are  heated — 1/273  °f  their  volume  for  each  degree 
centigrade.  Now  suppose  we  let  a  gas  expand  without 

63 


EVERYMAN'S   CHEMISTRY 

heating  it.  While  it  is  expanding  it  takes  up  heat 
instead  of  giving  it  off,  and  that  produces  cold.  When 
you  build  a  fire  under  a  boiler,  where  does  the  heat 
go?  A  little  of  it  goes  out  the  chimney,  and  the  rest 
is  taken  up  by  the  expanding  steam.  This  explains 
how  they  make  freezing-machines:  by  letting  lique- 
fied gases  evaporate  that  want  to  evaporate  so  badly 
that  they  don't  need  any  heat  to  drive  them  to  it. 
Then  they  use  up  what  heat  there  is.  In  a  similar 
way,  if  you  compress  a  gas,  not  by  cooling  it,  but  by 
force,  the  molecules  will  bombard  the  inclosing  walls 
harder  and  harder  until  they  grow  hot.  In  time  an 
equilibrium  is  reached,  but  dining  the  process  it  will 
give  off  the  heat  that  would  have  been  taken  from 
it  had  you  lowered  the  temperature. 

The  inventor  who  planned  to  maintain  a  very  high 
temperature  by  suddenly  compressing  hydrogen,  which 
is  the  lightest  gas,  and  then  "keep  up  the  temperature 
by  letting  that  hot  gas  escape,"  forgot  to  calculate 
that  as  much  cold  would  be  produced  by  the  expan- 
sion of  the  gas  as  there  would  be  heat  needed  for  its 
compression.  The  reason  why  it  makes  your  hand 
cold  to  blow  it  is  because  it  causes  the  moisture  to 
evaporate — to  expand  as  a  gas  and  to  produce  cold. 

Air  isn't  so  light,  after  all,  as  we  should  discover 
by  the  way  we  should  puff  out  and  our  organs  would 
all  be  disarranged  if  we  attempted  to  live  in  an 
atmosphere  containing  all  the  oxygen  we  need  but 
with  only  three  pounds'  pressure  to  the  square  inch — 
i.e.,  in  an  atmosphere  within  an  air-tight  room  from 
which  all  the  nitrogen  were  extracted.  Our  eyes 
would  pop  out  and  we  should  burst  blood-vessels  in 
no  time. 

A  very  interesting  and  highly  useful  discovery  was 
made  by  Dr.  F.  G.  Cottrell  while  professor  of  physical 

64 


AIR   AND   WATER 

chemistry  at  the  University  of  California.  He  found 
that  under  proper  conditions  electric  currents  of  very 
high  frequency  would  precipitate  particles  in  sus- 
pension in  the  air.  So  he  studied  and  worked  on  it 
according  to  his  nature,  whereby  with  great  eagerness 
he  sought  to  bring  down  big  game  that  no  other 
fellow  had  ever  bagged.  Then  he  covered  as  much  of 
the  art  as  he  could  with  patents. 

The  results  astounded  Doctor  Cottrell.  There 
were  the  smelter  people,  especially  the  copper  pro- 
ducers, in  the  throes  of  distress,  because  in  treating 
the  sulphurous  copper  ores  they  were  either  sending 
forth  sulphurous  fumes  that  killed  all  vegetation  for 
miles  around  or  they  were  wasting  vast  fortunes  in 
valuable  metal  dust  that  left  their  stacks  and  settled 
down  upon  the  earth  like  the  ashes  of  an  active  vol- 
cano. The  Government  was  after  them,  and  the 
farmers  were  making  themselves  heard  with  voices 
of  righteous  wrath.  So  they  fell  upon  Doctor  Cottrell's 
neck,  beseeching  him  to  save  them.  The  Cottrell 
process  does  not  precipitate  gases,  and  so  the  SO2 
goes  its  way.  But  by  this  process  the  particles  of 
metal  and  earthen  dust  are  removed  from  the  gases 
while  they  are  still  hot,  whereas  by  all  other  efforts  to 
collect  the  dust  from  gases  it  was  necessary  to  cool 
them  first.  Now  the  hot  gases,  emerging  from  the 
stack  in  that  condition,  continue  to  expand  until 
they  are  cooled  off,  by  which  time  they  are  too  dilute 
to  do  much  harm  and  are  very  likely  to  be  blown  away. 
The  sulphur  gas,  if  cool  when  it  comes  from  the  stack, 
will  sink  right  down,  because  it  is  heavy — and  then 
the  trouble  begins. 

Details  had  to  be  worked  out,  but  there  was  the 
art  established  of  precipitating  particles  in  suspension 
and  thus  saving  thousands  of  dollars  daily  in  single 

65 


EVERYMAN'S   CHEMISTRY 

plants,  and  letting  the  gases  escape  hot  from  the 
chimneys.  The  royalties  bade  fair  to  make  a  million- 
aire of  Doctor  Cottrell  in  short  order — but  who  wants 
to  be  a  millionaire?  It  is,  after  all,  a  good  deal  of  a 
nuisance  to  be  rich.  It  does  not  seem  to  improve 
the  characters  of  young  people  to  leave  them  big 
pots  of  money.  The  art  of  cooking  has  not  developed 
or  improved  since  the  days  of  Rome,  although  it  is 
a  chemical  process;  and  as  for  sleeping,  a  little  house 
is  as  comfortable  as  a  big  one.  The  administration 
of  a  fortune  takes  up  a  good  deal  of  time  and  dis- 
turbs one's  attention.  Of  course,  we  can  keep  some 
friends  by  means  of  it,  but  those  who  need  help  most 
are  the  very  men  who  will  need  it  again — and  perhaps 
be  no  better  for  it.  Anyway  you  can  put  it,  it  is  an 
infernal  nuisance  to  be  rich.  Getting  the  big  thing 
done  is  the  real  fun,  the  real  sport,  and  so  Doctor 
Cottrell  organized  a  good  working  laboratory  in  Cali- 
fornia to  treat  with  the  smelter  managers  and  work 
out  their  problems  in  consideration  of  fat  royalties, 
and  then  came  to  New  York  and  organized  the 
Research  Corporation,  to  engage  in  scientific  research. 
The  stock  can  pay  no  dividends,  and  is  held  by  men 
of  consequence  for  the  Smithsonian  Institution.  He 
turned  over  the  royalties  from  all  but  three- Pacific 
coast  States  to  the  Corporation,  and  used  the  proceeds 
coming  in  to  him  from  the  excepted  territory  to  start 
the  thing.  Then,  when  all  was  in  order,  he  turned 
over  the  rights  to  the  excepted  States,  also  to  the 
Research  Corporation,  and  took  a  job  in  the  Bureau 
of  Mines.  It  was  work  that  he  liked,  and  the  salary 
gave  him  a  fair  living. 

The  need  of  this  process  of  electric  precipitation  of 
particles  in  suspension  is  already  very  wide-spread. 
As  only  one  result  of  its  application,  enormous  savings 

66 


AIR   AND    WATER 

have  been  made  in  metallurgy  and  the  nuisance  of 
sulphur  fumes  greatly  decreased.  Where  the  condi- 
tions and  situation  warrant  it,  the  sulphurous  gas 
SO2  may  be  worked  over  into  sulphuric  acid,  as  you 
may  learn  later  under  sulphur,  but  this  is  not  feasible 
where  the  transportation  charges  for  sulphuric  acid 
are  too  great. 

The  possibilities  of  electric  precipitation  have  not 
been  nearly  reached  yet,  and  the  Research  Corpora- 
tion is  working  on  them.  The  fumes  of  iron  blast 
furnaces,  for  instance,  contain,  among  other  things, 
considerable  potash,  and  by  putting  high  potash 
feldspar  into  the  charge — another  suggestion  from 
Doctor  Cottrell's  fertile  mind — it  may  result  in  better 
iron,  more  free  from  sulphur,  and  the  precipitation  of 
a  large  quantity  of  the  much-needed  potash.  It  is 
also  possible  that  fog  may  be  dissipated  by  it,  by 
operating  an  electrically  propelled  kite  or  toy  aero- 
plane, fastened  by  long  wires  to  the  bow  of  a  ship, 
and  between  the  two  poles  on  the  aeroplane  and  at 
the  bow,  precipitating  the  fog  at  sea  that  is  in  the  path 
of  the  steamship.  At  least,  this  is  a  possibility. 

There  are  vast  potentialities  of  power  in  compressed 
air;  a  whole  undiscovered  realm  is  in  this.  And 
with  steady  winds,  such  as  we  have  over  so  much  of 
this  country,  it  does  seem  as  though  we  were  "not 
very  bright"  to  use  so  little  of  it  for  power,  doesn't 
it  ?  The  wind  is  there,  and  so  is  the  power ;  and,  with 
all  our  great  inventive  genius,  we  manage  to  pump 
up  a  little  water  for  the  cows!  So  we  had  better  order 
some  more  coal  to  grind  the  feed. 

Hydrogen  is  the  lightest  of  the  elements;  so  light 
that  its  atomic  weight  is  fixed  at  one,  and  the  atomic 
weight  of  the  other  elements  are  multiples  of  the 
weight  of  hydrogen.  Refinements  of  research  have 

67 


EVERYMAN'S    CHEMISTRY 

resulted  in  fixing  16  as  the  atomic  weight  of  oxygen, 
and  hydrogen  then  shows  1.008  instead  of  i  in  its 
combinations;  but  we  shall  not  concern  ourselves 
about  this. 

Hydrogen  has  been  found  in  a  free  state  in  nature, 
but  only  in  minute  quantities.  Most  of  it  that  is 
freed  soon  combines  with  oxygen  to  produce  water. 

Hydrogen  is  very  widely  used  in  chemical  industry. 
It  is  easily  prepared  by  the  electrolysis  of  water, 
H2O,  which  gives  two  volumes  of  hydrogen  for  every 
one  of  oxygen.  Still  another  way  is  to  pass  steam 
over  finely  divided  iron  or  over  certain  iron  ores  that 
are  short  of  all  the  oxygen  that  they  can  carry  in 
combination,  heated  to  a  white  glow.  The  steam 
decomposes  to  oxygen  and  hydrogen.  The  oxygen 
is  taken  up  by  the  ore,  and  the  hydrogen  passes  on 
through  the  tubes  from  which  it  is  collected.  Formerly 
the  ore,  lean  in  oxygen,  was  imported  from  Germany, 
but  with  the  ports  closed  on  account  of  the  war,  it 
seemed  worth  while  to  look  around  a  little.  In  Vir- 
ginia an  ore  better  than  the  imported  was  found. 

It  is  also  produced  by  the  action  of  many  acids 
upon  metals.  Let  us  consider  a  reaction  we  employed 
once  before — zinc  and  sulphuric  acid: 

Zn     +    H2SO4     =     ZnSO4     +     H2 
zinc        sulphuric  zinc         hydrogen 

acid  sulphate 

The  hydrogen  is  set  free,  and,  inasmuch  as  there 
is  nothing  for  it  to  combine  with,  it  floats  off  into  the 
air.  After  it  gets  there  we  know  very  well  what  will 
happen  to  it. 

The  ubiquity  of  water  is  almost  as  great  as  oxygen. 
In  the  form  of  water  vapor  it  is  mixed  with  air.  In 
Samuel  S.  Sadtler's  interesting  book  Chemistry  of 

68 


AIR   AND    WATER 

Familiar  Things  he  gives  the  number  of  grains  of 
water  that  one  cubic  yard  of  air  will  contain  as  the 
maximum  of  humidity  at  various  temperatures  by 
the  Fahrenheit  scale.  Here  they  are: 

14  degrees.       26.8  grains.  68  degrees.  206.5  grains. 

32       "  58-6      "  86       "  362.1      " 

50      "  112.6      "  212      "  lib.  and    81 

He  adds  that  one  cubic  mile  of  air,  saturated  with 
moisture  at  95  degrees  Fahrenheit,  would  give  up 
140,000  tons  of  water  (say  35,000,000  gallons)  if 
cooled  to  32  degrees,  or  the  freezing-point. 

No  wonder  it  rains!  The  rays  of  the  sun,  which 
produce  no  heat  by  their  passage  through  space,  do 
produce  heat  by  their  passage  through  the  air,  and 
at  the  surface  of  the  earth,  where  the  greatest  density 
prevails,  the  greatest  heat  is  produced.  So  they 
vaporize  the  waters  of  the  sea  and  lakes  and  rivers 
until  the  air  becomes  more  or  less  saturated,  accord- 
ing to  its  temperature.  A  breeze  of  cold  air  up  in  the 
blue,  that  we  may  not  feel  at  all,  reduces  the  tempera- 
ture of  that  above  us  and  down  comes  the  rain. 

Water  is  the  great  natural  solvent  and  carrier. 
A  man  has  been  described  as  about  twelve  pounds 
of  ashes  and  eight  buckets  of  water.  A  watermelon 
is  ninety-six  to  ninety-eight  per  cent,  water. 

A  peculiar  and  very  important  trick  of  water  is 
that  just  as  it  freezes  it  expands  about  6  per  cent,  in 
volume  and  decreases  in  weight  or  density  in  pro- 
portion. That  is  why  ice  floats.  If  it  did  not  float, 
rivers  and  streams  would  freeze  solid  and— things 
would  be  different  in  the  spring ! 


Hydrogen  peroxide,  [  J ,  or  H2O2,  is  a  rather 


EVERYMAN'S    CHEMISTRY 

unstable  fluid,  usually  dispensed  in  dilute  solutions 
in  water,  from  which  the  extra  oxygen  atom  soon 
frees  itself  under  the  reaction  H2O2  =  H2O  -f-  O.  It 
is  the  well-known  oxidizing  agent  of  the  household 
medicine-chest,  and  it  really  is  an  excellent  antiseptic 
for  that  reason.  We  put  it  on  a  sore  finger  to  oxidize 
the  foulness,  to  burn  it  up  without  appreciable  heat. 

Water  has  remarkable  properties.  It  behaves  very 
like  an  element  in  many  respects.  It  makes  innu- 
merable chemical  combinations  with  other  bodies. 
Many  bodies  will  dissolve  in  water  and  crystallize  out 
as  hydrates  which  are  compounds  with  water.  For 
instance,  washing-soda,  which  is  sodium  carbonate, 
Na2CO3,  is  a  white,  amorphous  powder  by  itself,  but  it 
will  combine  with  water  and  go  hot  in  the  process  un- 
til the  decahydrate,  which  means  the  tenfold  hydrate 
of  sodium  carbonate,  is  formed  and  this  is  expressed 
as  Na2CO3.ioH2O — that  is,  ten  molecules  of  water  to 
one  of  soda .  These  crystals  are  known  in  every  kitchen . 
Copper  sulphate  by  itself  is  a  white  substance  which 
crystallizes  in  colorless  needle-like  prisms.  It  will 
combine  with  water,  five  to  one,  to  make  the  penta- 
hydrate,  or  fivefold  hydrate  (CuSO4.sH2O)  which 
crystallizes  in  big  blue  crystals  of  an  entirely  different 
shape  and  popularly  known  as  blue  vitriol.  Heat 
will  drive  the  water  off. 

We  often  speak  of  hard  and  soft  water,  and,  while 
we  know  the  difference  in  practice,  we  are  not  all  of 
us  acquainted  with  the  philosophy  of  it.  There  are 
two  metals,  calcium  and  magnesium,  that  are  related 
to  each  other  in  the  periodic  system,  and  they  have 
certain  qualities  in  common.  Calcium  oxide,  CaO, 
is  lime,  and  magnesium  oxide,  MgO,  is  magnesia, 
and  neither  is  very  soluble  in  water.  Both  build 
salts  with  carbonic  acid.  By  contact  with  the  rocks 

70 


AIR   AND    WATER 

the  water  with  carbon  dioxide,  C02,  in  solution,  takes 
up  some  of  these  metals  and  carries  them  in  solution 
as  bicarbonates.  Now,  roughly  speaking,  the  bicar- 
bonates  are  soluble,  while  the  carbonates  are  not;  so 
if  you  boil  the  water  you  shift  the  bicarbonates  over 
into  carbonates — and  down  comes  boiler  scale:  your 
carbonates  of  lime  and  magnesium,  plus  mud  held  in 
the  water  in  suspension.  This  is  what  is  called  tem- 
porary hardness — the  bicarbonates  of  these  two  metals 
in  solution  that  precipitate  or  fall  down  as  insoluble 
carbonates  when  the  water  is  boiled.  But  there  is 
what  is  known  as  permanent  hardness,  when  the 
water  contains  the  chlorides  and  sulphuric  acid  salts 
of  these  metals.  Boiling  will  not  bring  them  down. 
And  yet,  in  proportion  as  the  water  contains  salts 
of  calcium  or  magnesium,  it  is  called  hard.  The  Ger- 
man scale  is  universally  used  as  to  the  hardness  of 
water;  one  degree  of  hardness  represents  one  part  of 
lime  in  100,000  parts  of  water,  two  degrees  is  double 
that,  etc.  Water  of  no  more  than  three  degrees  of 
hardness  is  generally  held  to  be  pretty  soft.  But 
we  do  not  want  any  lime  or  magnesia  in  water  for 
many  industrial  purposes,  whether  in  a  soluble  form 
or  not.  In  washing,  bleaching,  scouring,  dyeing — in 
nearly  all  textile  works — soap  is  used.  In  laundries 
and  households  we  use  it,  too.  But  what  is  soap? 
It  is,  as  a  good  example,  stearate  of  soda  (stearic  acid 
is  a  fatty  acid).  It  is  soluble  in  water.  But  if  the 
water  contains  calcium  or  magnesium  there  is  imme- 
diately produced  calcium  and  magnesium  soaps,  which 
are  insoluble.  The  stearic  acid  shifts  over  to  all  the 
Ca  and  Mg  that  is  in  the  water,  and  we  have  useless 
lime  or  magnesium  soap,  which  makes  a  gray  ring  on 
the  bath-tub,  streaks  the  clothes  in  the  laundry,  con- 
fuses the  dyer,  and  costs  all  sorts  of  money  in  wool- 
6  71 


EVERYMAN'S    CHEMISTRY 

scouring  and  in  the  bleaching  industries  by  sheer  waste 
of  soap.  West  of  England  woolens  have  a  good  repu- 
tation primarily  because  the  water  there  is  soft — - 
about  three  degrees  of  hardness  being  the  average. 
Calcium  and  magnesium  are  not  wanted  in  water  used 
in  the  industries. 

We  need  not  enter  into  a  discussion  of  the  nuisance 
that  hard  water  is  in  boilers ;  the  scale  ruins  the  tubes, 
and  it  is  such  a  poor  conductor  of  heat  that  it  runs 
the  coal  consumption  away  up.  There  are  all  sorts  of 
compounds  sold  to  prevent  boiler  scale,  and  they  are 
usually,  if  they  have  any  merit  at  all,  designed  to 
act  chemically  on  the  water  and  produce  a  scale  that 
is  lighter  and  more  porous  and  so  more  easily  removed. 
Such  compounds  are  soda  ash,  tannin,  caustic  soda, 
and  also  some  acids.  Others  act  mechanically  on  the 
particles  of  scale  as  they  form,  and  surround  them  with 
a  slippery  film  to  keep  the  mass  from  hardening  or 
cementing  together.  Such  compounds  are  slippery 
elm,  starch,  fats,  and  oils.  And  many  of  them  are 
out  and  out  quack  medicines.  Honey,  soap,  mercury, 
tobacco,  urine,  and  cow-dung  have  been  sold  as  won- 
derful practical  remedies. 

JThe  lime-soda  process  was  the  first  scientific  method 
introduced  to  make  hard  water  soft.  It  consists  of  a 
great  tank  for  settling,  and  smaller  tanks  for  reagents, 
with  a  view  to  bringing  down  the  soluble  salts  of  Ca 
and  Mg  as  insoluble  precipitates.  The  process  requires 
the  attention  of  a  chemist,  and  it  does  not  completely 
soften  the  water.  This  method  will  bring  water  down 
to  four  or  five  degrees  German  hardness — four  or 
five  parts  lime  or  magnesia  in  100,000  parts  of  water, 
but  not  lower. 

Now  comes  a  modern  invention  called  "permutit" 
that  is  chemically  interesting  and  is  of  great  useful- 

72 


AIR   AND   WATER 

ness.  Dr.  Robert  Cans,  of  the  German  Geological 
Survey,  while  studying  the  fertility  of  soils,  found 
that  certain  substances  known  as  zeolites  have  a  re- 
markable quality  of  swapping  bases  whenever  they 
find  a  chance  to  do  it.  They  take  up  potash,  then 
exchange  it  for  something  else  as  the  plants  are  ready 
for  the  potash,  then  exchange  that  something  else 
for  more  potash,  and  they  keep  it  up  indefinitely, 
feeding  potash  to  the  plants  in  this  manner.  Of  course, 
the  zeolites  of  the  soil  are  too  weak,  too  mixed  with 
other  things,  to  be  commercially  valuable,  so  he  pro- 
ceeded to  make  artificial  zeolite  by  fusing  feldspar, 
kaolin,  pearlash,  and  soda  together.  It  is  a  double 
silicate  of  aluminium  and  soda  with  water.  Graphically 
it  is  said  to  be  represented  by  the  following  formula: 


>^(OH), 


Si  /OH 

I\OA,X 

o  \ 

XO.Na 


sr  ^OH 

%i(OH)2 

I  pray  you  not  to  let  it  frighten  you.  You  observe 
those  two  Na  or  sodium  atoms  on  what  we  might 
call  the  eastern  boundary  ?  That  is  where  the  peculiar- 
ity lies.  If  you  bring  a  solution  containing  magnesium 
or  calcium  into  contact  with  it,  it  will  exchange 
sodium  for  Mg  or  Ca,  and  then,  if  you  bring  another 
salt  around,  it  will  exchange  its  Mg  or  Ca  for  the  base 
contained  in  the  new  solution.  It  has,  in  other  words, 

73 


EVERYMAN'S    CHEMISTRY 

no  principles  of  loyalty,  no  faithfulness,  no  morals 
whatever.  We  are  accustomed  to  polygamy  in  chem- 
istry; it  does  not  shock  us,  but  this  "  power  of  ex- 
change" is  unique. 

Now  let  us  apply  this  quality  to  our  own  use.  An 
upright  cylinder  contains  a  layer  of  marble  chips 
over  a  perforated  bottom  in  its  upper  part.  Below 
this  is  an  air  space,  and  then  comes  a  thick  layer  of 
permutit,  which  is  a  substance  very  like  soapstone 
in  appearance,  being  very  porous.  This  also  rests  on 
a  perforated  bottom,  and  under  it  is  a  layer  of  gravel. 
The  water,  in  passing  through  this  filter,  exchanges 
every  particle  of  its  lime  and  magnesia  for  sodium, 
in  whatever  form  these  may  be.  It  makes  the  shift, 
and  at  the  end  of  the  day  (according  to  its  computed 
capacity)  you  have  a  lime  and  magnesium  permutit 
in  the  filter  instead  of  a  sodium  permutit,  as  in  the 
morning.  The  water  that  has  passed  through  it  is 
completely  soft;  it  is  of  zero  hardness.  In  the  place 
of  all  its  Ca  and  Mg  it  contains  soluble  Na  salts. 
Soap  is  not  wasted  in  it,  boiler  scale  does  not  form, 
and  the  water  problem,  in  many  cases,  so  far  as  hard- 
ness is  concerned,  is  settled.  But  the  filter  is  to  be 
used  next  day,  and  the  permutit,  being  combined  with 
Ca  and  Mg,  has  nothing  to  exchange  for  these  ele- 
ments. So  we  flush  out  the  filter  by  forcing  water 
through  it  backward  for  a  few  minutes  and  then 
make  a  lo-per-cent.  solution  of  ordinary  cooking  salt 
(chloride  of  sodium,  NaCl)  in  water.  This  we  let 
stand  in  the  filter  during  the  night,  and  by  morning 
the  water  in  it  has  become  exceedingly  hard  and  the 
permutit  has  become  sodium  permutit  and  is  ready 
for  business  again  to  soften  water.  The  permutit  is 
not  soluble  in  water;  it  will  only  exchange  bases  with 
salts  in  solution.  So  it  is  not  wasted,  it  does  not  get 

74 


AIR   AND    WATER 

tired  as  some  catalysts  do,  and  it  lasts  permanently, 
day  in  and  day  out,  making  its  perpetual  exchange. 
The  amount  of  salt  required  to  regenerate  the  per- 
mutit  is  about  one  pound  of  salt  for  every  one  hundred 
gallons  of  hard  water  softened.  It  is  a  very  pretty 
operation,  and  as  useful  in  the  household  to  produce 
the  luxury  of  soft  water  as  it  is  in  the  industries. 

Iron  and  manganese  are  also  troublesome  factors 
in  water.  Both  make  stains  on  cloth.  These  are  re- 
moved by  oxidation,  the  higher  oxides  of  these  metals 
being  insoluble.  There  is  a  modification  of  permutit 
which  also  removes  them. 

Manganese  especially  is  not  desired  in  city  water- 
supplies.  So  far  as  we  know,  its  presence  does  not 
seem  to  affect  the  health  of  persons  who  drink  water 
which  contains  it,  even  when  we  consider  mineral 
waters  that  are  high  in  manganese  content.  But  it 
is  a  nuisance — worse  than  iron.  Certain  microscopic 
growths  found  in  water-pipes  absorb  the  manganese 
into  their  sheaths  and  form  long,  fibrous,  gelatinous 
masses  which  increase  the  friction  of  the  water,  and 
when  they  are  loosened  by  heavy  currents  the  water 
issues  from  the  faucets  in  an  unsightly  condition.  It 
is  deadly  to  fish  life.  The  brownish  cast  of  the  water 
shuts  out  the  sunlight  and  stunts  the  fish  growth, 
and  the  oxide  of  manganese  accumulates  in  and  clogs 
up  the  fish-gills.  Like  iron,  in  laundries  it  produces 
brownish  streaks  that  show  on  ironing,  and  in  bleach- 
eries  it  produces  a  muddy-white  color  and  occasionally 
brownish  spots.  It  will  do  the  same  to  the  finer 
classes  of  white  paper  if  employed  in  paper-mills. 
It  injures  the  fermentation  processes  of  breweries, 
and  it  spoils  the  color  baths  of  dye-houses. 

A  great  contribution  to  the  health  of  cities  and 
villages  has  been  found  in  the  addition  of  a  slight 

75 


EVERYMAN'S   CHEMISTRY 

amount  of  chlorine  to  the  water-supply.  Since  the 
adoption  of  the  chlorination  system  by  the  New  York 
City  department  of  water-supply,  not  a  single  case  of 
typhoid  fever  has  been  attributed  to  city  water. 

Another  method  of  destroying  bacteria  in  water  is  by 
submitting  it  to  the  action  of  ultra-violet  rays.  These 
are  rays  that  are  substantially  light  rays — or  rather 
would  produce  light  if  our  eyes  were  equipped  to 
observe  them.  They  are  the  burning,  actinic  rays  of 
the  sun — the  freckle  rays  and  sunburn  rays.  The 
method  is  to  use  a  mercury  arc-light  which  produces 
many  ultra-violet  rays,  but  which  cannot  get  through 
glass.  They  do,  however,  go  right  through  quartz. 
So  the  Peter  Cooper  Hewitt  mercury  arc  light  is  pro- 
duced in  a  quartz  tube  and  then  water  is  run  over  the 
tube. 


VII 

MORE  ABOUT  AIR 

Nitrogen — Its  Inertia — Nature's  Subtle  Art — The  Need  of  Fixed 
Nitrogen — Its  Satanic  Tricks— The  Lean  Man  and  the  Fat 
One — The  History  of  an  American  Invention — How  the  Great 
War  was  Made  Possible — A  New  Method  of  Fixing  Nitrogen 
that  is  Full  of  Promise — Ammonia — Nitric  Acid — Why  Explo- 
sives Explode 

NITROGEN,  N,  is  a  gas,  a  little  lighter  than  oxy- 
gen— in  the  ratio  of  14  to  16 — and  it  comprises 
about  four-fifths  of  the  air.  There  is  enough  going  on 
in  the  air  to  keep  it  pretty  well  mixed.  We  have  al- 
ready spoken  of  how  inert  this  nitrogen  gas  is.  We 
breathe  in  the  air,  take  up  the  oxygen  (of  which  nearly 
all  of  the  other  fifth  is  composed),  and  breathe  out 
the  same  nitrogen,  but  not  the  same  oxygen.  In  the 
exhalations  the  nitrogen  is  mixed  with  some  oxygen 
and  carbon  dioxide,  or  carbonic-acid  gas,  instead  of 
all  of  the  oxygen  that  went  in.  Nothing  happens  to 
the  nitrogen.  Its  atoms  are  clinched  together  in  pairs 
as  molecules,  and  they  will  not  loosen  up  under  ordi- 
nary conditions.  In  a  temperature  such  as  is  tradi- 
tionally held  by  orthodoxy  to  be  reserved  for  sinners, 
we  should  have  an  entirely  different  chemistry  of 
every-day  life;  for  extreme  heat,  such  as  is  found  in 
the  electric  sparkfc  will  tear  the  nitrogen  molecule 
apart,  and  when  nitrogen  once  begins  to  react,  the 
cosmic  fur  may  be  said  to  fly. 

77 


EVERYMAN'S   CHEMISTRY 

Nature  in  its  quiet  way  performs  the  most  difficult 
laboratory  tricks  without  any  noise  or  explosion.  I 
have  said  that  it  is  very  hard  to  get  nitrogen  from 
the  air  into  combination.  I  meant  in  the  laboratory 
or  in  the  works.  On  the  other  hand,  clover,  cow- 
peas,  and  other  leguminous  plants  have  little  nodules 
on  their  stems  just  above  the  earth,  and  these  nodules 
swarm  with  harmless  bacteria  which  take  the  nitrogen 
from  the  air,  bring  it  into  combination,  and  feed  it  to 
the  plant.  Plow  under  your  cow-peas  or  clover  and 
you  will  have  provided  your  soil  with  fixed  nitrogen. 
This  is  the  good  old  standard  way  to  get  fixed  or 
combined  nitrogen  into  the  soil.  The  only  objections 
to  it  are  the  need  to  hurry  up,  the  demand  for  farm 
produce  from  increasing  urban  populations,  the  desire 
of  the  farmer  to  exchange  produce  for  wealth,  and 
the  sleepless  mortgage. 

Aside  from  taking  up  nitrogen  from  the  air,  nature 
has  a  way  of  giving  it  back.  There  are  a  few  chemical 
reactions  that  give  off  free  nitrogen  out  of  combination, 
but  it  is  quite  a  laboratory  trick  to  perform  them. 
Nature,  on  the  other  hand,  seems  to  give  it  off  in 
some  sort  of  a  cycle,  taking  it  up  by  means  of  bacteria, 
and  giving  some  of  it  off  again  when  the  plants  and 
animals  are  carbonized ;  and  there  may  be  —  who 
knows? — some  bacteria  that  consume  nitrates  and 
set  nitrogen  free.  There  must  be  a  nitrogen  cycle,  into 
life  and  back  again. 

But  there  we  are.  We  must  have  nitrogen  in  com- 
bination for  fertilizer  and  so  for  food,  for  clothing, 
for  explosives,  for  mining,  and  for  all  sorts  of  engi- 
neering work  and  for  munitions  of  war,  for  dye- 
stuffs,  and  hundreds  of  other  things.  Some  foods, 
such  as  sugar,  starch,  and  fats,  contain  no  nitrogen, 
but  the  proteins,  the  stuff  that  builds  muscle  and 

78 


MORE   ABOUT   AIR 

brawn,  the  meat  for  strong  men,  all  these  contain 
nitrogen. 

Of  course,  there  is  the  great  waste  of  city  sewage, 
which  contains  enormous  quantities  of  nitrogen  in 
combination,  and  we  know  how  to  turn  it  all  into  in- 
offensive and  useful  products.  I  say  we  know  how, 
but  we  have  not,  all  of  us,  these  facts  of  chemistry 
alive  in  our  brains,  and  so  we  just  go  on  complaining 
and  wondering  why  somebody  doesn't  do  something. 

Let  us  now  consider  a  little  more  of  this  remarkable 
element.  It  can  outdo  fire  and  brimstone  in  its 
satanic  tricks.  It  will  not  combine  except  in  its  own 
secret  way,  and  once  it  gets  into  combination  it  be- 
comes the  business  end  of  nearly  all  explosives,  and 
it  is  one  of  the  elements  which  must  be  present  in 
combination  if  life  is  to  prevail.  In  the  eggs  of  all 
animals  it  is  present  in  large  proportion.  I  shall  not 
offer  to  base  any  conclusions  upon  this,  but  merely 
give  it  as  a  fact,  that  the  thin,  wiry  little  man,  who 
is  all  nerves  and  action,  contains  more  nitrogen  in 
proportion  to  his  weight  than  the  obese,  fat  man. 
It  is  present  in  all  nerve  stuff. 

Until  lately  the  only  place  to  get  nitrogen  in  com- 
bination was  from  the  great  nitrate-of-soda  beds  of 
Chile.  Ammonia  is  obtained  from  the  distillation  of 
coal,  but  not  in  sufficient  quantities.  This  source 
of  supply  is  increasing  as  by-product  coke-ovens  are 
built.  That  comes  from  the  N  left  over  in  the  plants 
during  the  ages.  We  can  get  it  into  the  earth  by 
planting  leguminous  plants  and  plowing  them  under, 
as  we  have  noted,  but  for  manufacturing  purposes 
the  Chilean  nitrate  beds  were  practically  the  only 
source  of  supply.  This  is  what  has  made  Chile  so  rich. 

But  that  store  will  not  last  forever.  The  best  posted 
persons  say  that  at  the  present  rate  of  consumption 

79 


EVERYMAN'S   CHEMISTRY 

it  should  take  from  a  hundred  to  a  hundred  and  fifty 
years  to  exhaust  the  supply,  and  for  the  past  twenty- 
five  or  thirty  years  the  problem  of  " fixing  nitrogen,"  as 
it  is  called,  has  been  one  of  the  chemical  prizes.  As 
soon  as  nitrogen  is  in  combination  it  is  fixed,  and  the 
chemist  feels  that  he  can  negotiate  with  it. 

An  American,  Charles  S.  Bradley,  was  the  first  to 
combine  nitrogen  and  oxygen  from  the  air  on  a  factory 
scale  by  means  of  an  electric  arc  at  Niagara  Falls. 
He  made  considerable  progress,  developed  the  art,  in 
fact,  but  he  had  the  misfortune  to  be  first  in  the 
field.  American  capital  has  never  been  favorably  dis- 
posed toward  experiment  except  in  mechanics,  and 
at  the  point  that  Bradley  had  to  stop  for  lack  of  funds 
two  Norwegian  chemists,  Birkeland  and  Eyde,  took 
up  the  problem.  With  the  greater  water-power 
available  in  Norway,  and  with  abundant  capital  from 
Europe,  they  have  had  enormous  success.  Before 
the  Panama  Canal  was  opened  their  ships  with  nitro- 
gen fertilizer  sailed  from  Norway  around  Cape  Horn 
and  past  Chile  to  the  west  coast  of  the  United  States 
with  their  product.  They  make  a  combination  of 
nitrogen  with  lime  for  fertilizer. 

Then  the  Germans  took  hold  of  it,  and  we  shall  see 
what  happened.  The  results  are  not  due  to  any  special 
superiority  of  German  chemists  over  others.  The 
merit  of  a  chemist  depends  upon  the  man,  not  his 
nationality.  We  may  hold  this  fact  to  be  self-evident, 
but  there  are  a  great  many  of  us  who  do  not  seem  to 
have  grasped  it  yet.  Of  course  there  are  more  chem- 
ists in  Germany  than  there  are  elsewhere  in  propor- 
tion to  the  population,  and  I  think  it  true  that  the 
profession  has  a  better  social  standing  there  than  in 
other  countries.  This  may  sound  like  tea-parties  and 
dances,  but  it  means  directorates  and  banking  connec- 

80 


MORE  ABOUT   AIR 

tions.  The  main  feature,  however,  is  that  German 
business  men  are  not  afraid  of  that  bugaboo  of  his 
American  cousin,  to- wit,  "the  theorist."  American 
capitalists  will  take  up  an  engineering  problem  and 
look  over  blue-prints  and  plotted  curves  which  they 
do  not  completely  understand,  but  which  they  will 
try  to  grasp,  and  as  soon  as  they  get  the  idea  of  what 
is  to  be  accomplished  and  a  theory  of  the  method, 
down  comes  the  telephone  receiver,  and  a  syndicate 
is  formed.  The  money  is  straightway  available.  If 
the  problem  is  a  chemical  one,  it  has  been  his  habit 
to  close  his  mind  and  his  eye  and  to  have  nothing  to 
do  with  it,  whereas  his  counterpart  in  Germany  would 
go  at  the  proposal  with  the  same  lively  curiosity  and 
interest  that  he  would  display  in  response  to  a  pro- 
posal in  engineering.  The  result  is  that  the  American 
business  man  has  neither  experience  in,  nor  knowledge 
of,  chemistry.  He  cannot  tell  one  chemist  from  an- 
other. He  doesn't  even  know  where  to  go  to  find  out. 
Not  long  ago  some  Eastern  capitalists  took  under 
consideration  a  large  investment  in  a  chemical  works 
engaged  in  the  utmost  niceties  of  chemical  manufact- 
ure. The  processes  were  involved  and  exceedingly 
complex.  So,  in  order  to  get  at  the  bottom  facts 
concerning  the  industry  and  the  way  the  problems 
were  met,  they  sent  a  civil  engineer  out  to  examine 
it.  They  might  as  well  have  sent  a  dentist! 

Now  let  us  get  at  the  way  the  Herren  Doctoren 
Haber  and  le  Rossignol  solved  their  part  of  the  prob- 
lem. There  is  very  little  water-power  in  Germany, 
but  catalysis  is  an  art,  and  it  is  available  everywhere. 
They  knew,  as  every  chemist  has  known  for  years, 
that  if  three  volumes  of  hydrogen  gas  and  one  volume 
of  nitrogen  are  inclosed  in  a  vessel  and  an  electric 
spark  is  passed  through  the  mixed  gases,  a  little 

81 


EVERYMAN'S    CHEMISTRY 

ammonia  will  be  formed.  Ammonia  is  three  hydrogen 
atoms  hooked  on  to  one  nitrogen  atom.  Its  symbol 
is  NH3.  Not  much  ammonia  will  be  formed,  though, 
and  for  this  reason:  at  the  temperature  of  the  elec- 
tric spark,  nitrogen  and  hydrogen  will  unite  to  form 
ammonia,  but,  at  the  same  time,  ammonia  is  not  stable 
at  that  temperature.  It  will  decompose  into  nitrogen 
and  hydrogen.  It  is  reversible  reaction,  because  it 
works  both  ways.  It  is  expressed  as  follows: 

N2    +    3H2     ^ 2NH8 

nitro-      hydro-  f     ammonia 

gen  gen 

But  they  did  not  want  a  reversible  reaction;  they 
wanted  the  straight  reaction,  one  in  which  the  arrow 
points  in  one  direction  only,  and  not  both  ways. 

N    +    3H — >NH3 

nitro-      hydro-       ammo- 
gen  gen  nia 

So  they  conceived  the  happy  idea  of  sending  one 
part  of  nitrogen  and  three  parts  of  hydrogen  through 
tubes  containing  various  metals  with  a  view  to  getting 
the  metals  to  act  as  catalysts.  Osmium  and  uranium 
did  it.  Details  of  the  process  are  secret,  but  by  1913 
an  enormous  plant,  costing  $10,000,000,  had  been 
erected  and  was  in  full  operation  at  Ludwigshafen. 
The  nitrogen  is  obtained  by  making  liquid  air  and 
distilling  it  off  while  the  hydrogen  is  obtainable  in 
many  ways.  This  gave  Germany  all  the  combined 
nitrogen  it  might  care  to  produce  by  adding  the  units 
already  established,  in  the  form,  you  observe,  of 
ammonia. 

It  never  rains  but  it  pours.    When  one  process  is 
developed,  another  is  likely  to  follow  shortly  after- 

82 


MORE   ABOUT   AIR 

ward.  An  American  chemist,  Willson,  started  to 
make  calcium  carbide  years  ago  at  Niagara  Falls  by 
treating  coke  and  quicklime  in  an  electric  current. 
It  takes  considerable  power  to  bring  this  about,  but 
only  one-fifth  as  much  as  is  required  to  fix  atmospheric 
nitrogen  by  the  Norwegian  process.  Calcium  carbide 
is  a  very  widely  known  chemical  to-day,  and  is  used 
to  make  acetylene  gas  for  lighting  houses,  for  automo- 
bile lights,  and  for  enriching  city  gas.  .The  reaction 
is  very  simple;  put  water  on  it,  and  the  product  is 
acetylene  gas  and  slacked  lime. 

Now  we  shall  strike  a  very  good  example  of  the 
international  nature  of  science,  of  how  an  invention  is 
started  in  one  country  and  developed  in  another.  Here 
we  have  calcium  carbide,  developed  in  the  United 
States.  Then  two  German  chemists,  Frank  and  Caro, 
discovered  that  if  you  heat  this  carbide  and  run  a 
current  of  nitrogen  over  it,  the  nitrogen  will  combine 
with  it  and  you  have  calcium  cyanamide,  which  is 
an  excellent  nitrogen  fertilizer.  Let's  put  these  two 
reactions  down: 


3C     +     CaO     =     CaCa     +     CO 
coke         quick-        calcium       carbon 
lime          carbide       monox- 
ide 

CaCa     +     Na     =     CaCN2     +     C 
calcium       nitro-         calcium          car- 
carbide         gen        cyanamide       bon 


The  extra  carbon  is  burned  away  in  the  heat,  and 
the  cyanamide  fertilizer  was  made  in  large  quantities 
in  Germany. 

Now  we  come  to  a  third  reaction  that  has  been 
known  for  a  long  time — that  superheated  steam  passed 

83 


EVERYMAN'S   CHEMISTRY 

over  calcium  cyanamide  gives  as  the  resultant  prod- 
ucts carbonate  of  lime,  or  limestone,  and  ammonia. 
Here  is  the  reaction: 


CaCN2     +     3H2O     *     CaCO3     +     2NH3 
calcium  water         carbonate      ammonia 

cyanamide  of  calcium 

So  here  were  two  methods  of  making  ammonia, 
and  from  the  way  in  which  the  output  of  calcium 
cyanamide  has  increased  in  Germany,  from  50,000  tons 
annually  before  the  war  to  600,000  tons  in  1916,  it 
would  appear  that  the  cyanamide  process  is  the 
cheaper  one. 

In  the  mean  time  the  great  Professor  Ostwald  had 
worked  out  a  method  of  turning  the  base  ammonia 
into  nitric  acid,  also  by  catalysis.  Nitric  acid  is  one 
nitrogen,  one  hydrogen,  and  three  oxygen  atoms  in 
the  molecule,  and  Professor  Ostwald  found  that  by 
passing  ammonia  and  oxygen  through  tubes  filled 
with  finely  divided  platinum  the  following  reaction 
takes  place  : 

NH3     +    2O2     =     HNO3     +    H2O 
am-          oxygen         nitric  water 

monia  acid 

Nitric  acid  is  the  one  thing  most  especially  needed 
to  make  explosives.  By  1915  Germany  within  her 
own  borders  had  developed  the  art  of  making  all  things 
needful  for  munitions  of  war  except  copper  and  cotton. 
Without  these  processes  the  war  could  not  have  lasted 
over  a  year,  despite  the  enormous  stores  of  Chilean 
nitrate  that  were  on  hand.  Indeed,  it  was  these  four 
processes  of  Willson,  of  Haber  and  le  Rossignol,  of 
Frank  and  Caro,  and  of  Ostwald  that  have  made  the 

84 


MORE   ABOUT   AIR 

war  endure.  Courage  would  have  been  of  no  avail 
without  them. 

Very  lately  Prof.  John  E.  Bucher,  of  Providence, 
Rhode  Island,  has  proposed  a  new  method.  His 
work  is  based  on  the  fact  that  nitrogen  will  combine 
with  an  alkali  and  carbon  in  the  presence  of  iron  as  a 
catalyst  and  produce  the  cyanide,  a  combination,  for 
instance,  of  sodium,  carbon,  and  nitrogen,  NaCN.  He 
brings  soda  ash  and  powdered  coal  together  with  pow- 
dered iron  or  iron  ore — either  will  do — in  a  furnace, 
runs  air  through  it  at  a  moderately  high  temperature, 
and  the  result  is  sodium  cyanide,  with  the  iron  uncom- 
bined.  No  electric  power  is  needed,  no  heavy  outlay, 
no  costly  materials;  the  whole  process,  apparently, 
may  be  carried  out  almost  anywhere  at  a  very  low 
cost. 

Of  course  everybody  knows  that  cyanide  of  soda 
is  not  a  thing  to  fool  with;  that  it  is  a  deadly  poison. 
But  by  treating  it  with  steam  the  products  become 
sodium  bicarbonate  and  ammonia.  Engineering  de- 
tails still  need  to  be  worked  out,  and  nothing  can  be 
called  a  success  until  it  succeeds  in  practice,  but  it 
is  not  more  than  fair  to  say  that  Doctor  Bucher  is 
busy  at  them.  If  the  difficulties  are  overcome,  it 
bids  fair  to  make  us  all  sit  up  and  take  notice. 

Now  let  us  study  the  combinations  of  this  absurd 
element  with  hydrogen  and  see  what  results  we  get. 
I  do  not  know  why  nitrogen  behaves  so.  There  is 
ammonia,  NH3.  It  has  an  avidity  for  water  which 
is  almost  insatiate.  But  when  you  have  NH3  dis- 
solved in  water  (H2O)  you  haven't  exactly  what  you 
might  think  you  have.  As  soon  as  the  ammonia 
reaches  water,  or  as  soon  as  you  start  a  chemical 
reaction  going,  the  nitrogen  in  the  ammonia  molecule 
brings  its  two  extra  hooks  or  bonds  into  play,  the 

85 


EVERYMAN'S   CHEMISTRY 

molecule  of  ammonia  combines  with  a  molecule  of 
water,  and  we  have  ammonium  hydroxide,  or  NH4OH. 
Let  us  put  it  down  graphically : 


Here  you  get  a  radical  or  tail  of  oxygen  and  hydro- 
gen just  like  the  OH  radical  in  caustic  soda  or  caustic 
potash,  and  it  behaves  that  way!  It  acts  just  like  a 
metal,  but  like  a  metal  with  one  bond.  Drive  it  out 
of  such  a  combination,  and  we  shall  find  that  the  nitro- 
gen has  only  three  hooks  again.  And  then,  having 
determined  that  ammonia  behaves  like  the  metals,  we 
should  expect  it  to  have  no  special  affinity  for  them. 
But  here  we  should  be  wrong  again,  for  it  attacks 
metals  with  energy,  just  as  an  acid  does,  giving  up 
its  hydrogen  and  forming  nitrides  of  metals.  That 
ide  in  nitride,  you  may  recall,  indicates  direct  combi- 
nations of  a  metal  with  nitrogen.  Nitrogen  makes 
other  compounds  with  hydrogen,  foolish  compounds 
which  it  has  no  business  to  make,  such  as  hydrazine, 
N2H4,  and  hydrazoic  acid,  NsH,  all  bristling  with  un- 
satisfied bonds.  Hydrazoic  acid  is  unstable,  and  very 
explosive  as  well. 

With  oxygen  it  forms  N20,  or  nitrous  oxide,  which 
is  laughing-gas,  and  is  largely  used  as  an  anesthetic. 
There  is  nitric  oxide,  NO,  which  is  unstable,  and  com- 
bines immediately  with  more  oxygen  to  form  nitro- 
gen dioxide,  NO2,  which  is  a  reddish  gas  and  violently 
poisonous.  Then  we  come  to  nitric  acid  anhydrid, 
N2O6,  which,  with  one  molecule  of  water  (H20),  makes 

86 


MORE   ABOUT   AIR 

two  molecules  of  nitric  acid  (HNO3),  one  of  the  most 
powerful  acids  known : 

N206  +  H20  =  2HN08 

" Acids,"  says  the  definition,  "have  one  or  more 
hydrogen  atoms  that  can  be  replaced  by  metals." 
All  right;  there's  nitric  acid,  but  there's  ammonia, 
NH3,  too,  which  is  not  an  acid.  Then  there's  the 
opposite:  "Bases,  or  alkalies,  include  compounds  of 
the  general  type  of  metal  having  an  OH  radical." 
Very  well;  there  is  ammonium  hydroxide,  NEUOH. 
But  why  does  nitrogen  work  both  ways?  From  the 
standpoint  of  a  lazy,  old-fashioned  chemist,  I  should 
say  that  nitrogen  has  no  chemical  conscience  whatever. 

Since  nitric  acid  has  so  much  to  do  with  explosives, 
we  might  as  well  consider  a  little  about  them  at  this 
point.  An  explosive  is  a  substance  that  is  capable  of 
liberating  large  quantities  of  gas  as  a  result  of  very 
rapid  chemical  action.  The  gases  set  free  by  the  ex- 
plosion of  gunpowder  occupy  about  three  hundred 
times  the  volume  of  the  powder,  and  the  heat  of  the 
explosion  expands  these  gases  many  times  more.  In 
gunpowder  the  carbon  and  oxygen  atoms  that  unite 
to  form  carbonic-acid  gas  and  other  bodies  are  in 
different  molecules,  and  the  explosion,  while  instanta- 
neous in  appearance,  is  not  so  rapid  as  dynamite. 
In  nitroglycerin  all  the  atoms  are  in  the  same  mole- 
cule, which  disintegrates  as  follows : 

4C3H6(ONO)3 >  I2C02     +     ioH2O     +     6N2     +     O2 

nitroglycerin  carbon  water  nitro-         oxy- 

dioxide  gen  gen 

These  gases  take  up  twelve  thousand  times  the  volume 
of  nitroglycerin  in  the  dynamite,  and  by  the  heat 
produced  are  expanded  nearly  eight  times  farther. 
So  one  cubic  inch  of  it  expands  about  nine  thousand 
times  in  an  instant.  No  wonder  it  shakes  things  up. 
7  87 


VIII 

THE   RED-HEADED   HALOGENS 

Fluorine,  Chlorine,  Bromine,  and  Iodine — Four  of  a  Kind,  with 
Differences — The  Young  Devil  and  the  Old  Man  with  a  Past — 
Muriatic  Acid — Salt — Great  Value  of  Chlorine — Purification  of 
Water — Uses  of  Fluorine,  Bromine,  and  Iodine 

HERE  is  a  family  of  elements,  legitimately  con- 
nected according  to  the  Periodic  Law,  that  be- 
have just  as  a  family  of  persons  or  elements  should 
behave.  We  are  wont  to  attribute  to  men  and  women 
having  auburn  hair  a  certain  quickness  in  response 
to  a  stimulus.  This  is  a  distinct  quality  of  the  halo- 
gens. As  the  persons  we  have  in  mind  grow  older  we 
observe  that  they  usually  grow  more  sedate  and 
circumspect.  As  the  halogens  increase  in  atomic 
weight  they  grow  more  biddable  and  quiet  in  their 
reactions.  Young  persons  adorned  with  Titian  locks, 
if  they  be  maids  or  young  matrons,  are  likely  to  wear 
green  gowns.  We  shall  find  this  taste  in  color  also 
indicated  among  the  halogens. 

They  are  fluorine,  chlorine,  bromine,  and  iodine. 
Their  atomic  weights  are,  in  the  order  named,  19, 
35>£,  80,  and  127.  In  the  same  order  they  are  gas, 
a  gas  twice  as  heavy,  a  liquid,  and  a  solid.  In  color 
they  are,  also  in  the  same  order,  greenish  yellow,  yel- 
lowish green,  brown,  and  violet-black.  All  of  them 
have  one  hook  or  affinity.  All  of  them  combine  with 

88 


THE    RED-HEADED   HALOGENS 

hydrogen  and  produce  acids,  and,  in  the  order  of 
their  atomic  weights,  their  liking  for  hydrogen  de- 
creases. Bring  fluorine  and  hydrogen  together,  even 
in  the  dark,  and  they  will  combine  to  HP,  or  hydro- 
fluoric acid,  with  explosive  violence.  The  real  acid 
would  be  hydrogen  fluoride,  HP,  with  water,  H2O; 
but  as  there  is  always  water  around  and  only  one 
hydrogen  atom  becomes  ionized,  we  call  HP  hydro- 
fluoric acid,  HC1  hydrochloric  acid,  etc.  Chlorine  and 
hydrogen  will  unite  under  the  influence  of  light. 
Bromine  will  unite  with  hydrogen  if  passed  through 
a  heated  tube  containing  platinum  gauze.  It  takes 
still  more  heat  in  the  presence  of  platinum  black  to 
do  the  same  with  iodine.  Then,  again,  fluorine  will 
drive  chlorine  out  of  combination  with  hydrogen  and 
take  its  place.  Chlorine  will  do  the  same  to  bromine, 
and  bromine  to  iodine.  Compounds  of  iodine  with 
hydrogen  are  not  very  stable,  but  you  can  hardly 
drive  fluorine  and  hydrogen  apart — until  HP  meets 
something  that  fluorine  likes  better,  as,  for  instance, 
an  alkali,  a  metal,  or  a  salt  with  a  weak  acid.  Then 
the  hydrogen  is  dropped,  and  the  fluorine  goes  at  it. 
We  might  say  that  fluorine  is  the  young  devil,  and 
iodine  is  the  old  man  with  a  past.  In  valency,  too, 
bromine  and  iodine  grow  a  little  irregular.  Occa- 
sionally they  develop  three,  five,  and  even  seven  bonds 
for  combining.  This  does  not  appear  to  be  the  case  with 
fluorine,  and  chlorine  seems  to  be  slightly  addicted 
to  allotropy,  but  we  do  not  know  much  about  that  yet. 
The  family  relations  toward  oxygen  are  the  very 
opposite.  Fluorine  does  not  combine  with  it.  Chlo- 
rine does,  but  the  compounds  are  very  unstable. 
Chlorate  of  potash,  for  instance,  gives  off  its  oxygen 
with  explosive  violence  in  the  presence  of  a  reducing 
agent.  Oxides  of  bromine  are  more  stable  than  those 

89 


EVERYMAN'S    CHEMISTRY 

of  chlorine,  and  those  of  iodine  are  more  stable  still. 
With  sulphur  they  behave  in  a  somewhat  similar 
manner. 

All  the  halogens  are  lively  in  their  reactions,  fluorine 
being  the  liveliest,  and  iodine  the  least  so. 

Fluorine,  because  it  bites  its  way  through  glass 
and  destroys  tissues  with  such  avidity  that  it  is  one 
of  the  rankest  of  poisons,  is  no  laboratory  favorite. 
Of  all  the  elements  it  has  the  strongest  tendency  to 
form  compounds.  It  is  found  in  nature  mostly  in 
rocks,  in  combination  with  calcium  as  fluorspar.  Its 
principal  use  is  for  etching  glass.  The  process  is 
interesting.  The  glass  vessel  which  is  to  be  etched  is 
covered  with  wax,  which  is  not  disturbed  by  the 
fluorine  or  by  hydrofluoric  acid.  The  desired  figures 
are  drawn  in  the  wax,  leaving  the  glass  bare  wherever 
the  lines  are.  Sulphuric  acid  will  drive  fluorine  out  of 
fluorspar,  producing  sulphate  of  calcium,  or  gypsum, 
on  the  one  hand,  and  hydrofluoric  acid  on  the  other. 
The  glass  is  attacked  wherever  a  line  is  drawn,  or 
wherever  the  wax  is  scraped  off.  An  opaque  surface 
is  produced.  If  the  hydrofluoric  acid  is  dissolved  in 
water,  and  the  glass,  prepared  in  the  same  way,  is 
dipped  into  the  solution,  the  acid  will  bite  out  a  shiny 
and  transparent  groove  wherever  the  glass  is  exposed. 
Ammonium  fluoride  (NH4F)  is  generally  employed 
in  the  place  of  fluorspar  in  the  glass  industry.  Another 
use  for  this  product  is  to  eat  the  silicates  out  of  straw 
and  then  limber  it  up  so  that  it  may  be  woven  into 
straw  hats. 

Chlorine  is  the  famous  member  of  the  family.  It 
is  of  very  widespread  occurrence.  In  combination 
with  sodium,  one  atom  of  each  in  the  molecule  as 
chloride  of  sodium  (NaCl),  it  is  what  we  know  as 
salt,  common  salt,  table  salt,  and  we  must  have  it. 

90 


THE   RED-HEADED   HALOGENS 

When  it  is  scarce  we  prize  it,  and  when  it  is  lacking 
we  will  brave  almost  any  danger  to  get  it.  I  do  not 
know  what  its  function  is  in  the  process  of  digestion, 
but  it  is  probable  that  the  hydrochloric  acid  which  we 
have  in  our  stomachs  is  prepared  from  salt  in  one  of 
that  series  of  co-ordinated  chemical  factories  that 
each  of  us  has  in  his  body.  Chlorine  is  everywhere  in 
varying  quantities — in  rocks,  in  the  earth,  in  the  sea, 
and  deposited  in  the  beds,  far  under  the  earth,  of  ex- 
tinct salt  lakes.  Nature  does  not  perform  a  cycle 
with  salt;  it  washes  it  into  the  sea  and  lets  it  stay 
there.  The  actual  process  seems  to  be  that  the  so- 
dium is  carried  to  the  sea  mostly  in  the  form  of  the 
sulphate,  and  the  calcium  or  lime  as  a  chloride,  and 
a  shift  in  the  acids  takes  place  after  a  while  in  the  sea- 
water,  the  calcium  chloride  becoming  calcium  sul- 
phate or  gypsum,  and  the  sodium  sulphate  becoming 
sodium  chloride.  The  sea  is  growing  richer  and  the 
earth  is  growing  poorer  in  salt.  But  we  need  not 
worry  about  it. 

Salt  is  the  raw  material  for  the  great  soda  industry, 
which  we  shall  treat  of  in  another  chapter.  It  is  also 
used  to  drive  other  bodies  out  of  solution  in  chemical 
industry. 

Like  all  other  members  of  the  family,  chlorine  com- 
bines with  hydrogen  as  hydrochloric  acid  or,  as  it  is 
often  called,  muriatic  acid,  one  atom  of  each  in  the 
molecule,  or  HC1.  It  is,  as  we  have  mentioned  before, 
not  really  an  acid  until  water  is  brought  to  it,  so  that 
the  proper  formula  would  be 

HC1  +  H2O  =  H3C1O 

But  we  write  it  HC1  because  the  water  stays  water 
and  the  one  H  ion  of  HC1  does  the  business.  HC1  is 

91 


EVERYMAN'S    CHEMISTRY 

a  gas,  very  soluble  in  water,  and  is  a  very  strong  acid. 
It  is  very  widely  used  to  produce  metallic  chlorides. 
Many  metals  are  dissolved  by  it.  It  has  wide-spread 
use  in  the  industries.  The  grape  sugar  works  take 
large  quantities  to  neutralize  the  lime  in  the  process. 
Some  steel-makers  use  it  for  " pickling,"  or  eating  off 
the  oxides,  or  rust,  from  manufactured  steel,  although 
sulphuric  acid  is  more  frequently  employed  for  this 
purpose. 

Chlorine  combines  with  oxygen,  always  to  form 
acids.  The  natural  combination  is  one  atom  of 
oxygen  to  two  of  chlorine  (because  of  the  oxygen's  two 
hooks  and  the  chlorine's  one),  or  chlorine  monoxide, 
C12O.  This  is  a  brownish  gas,  very  dangerous  and 
very  explosive,  breaking  up  easily  into  its  component 
parts.  Mix  it  with  water  and  you  get  a  solution  of 
hypochlorous  acid,  in  which  a  molecule  of  water  will 
combine  with  a  molecule  of  the  chlorine  monoxide 
to  form  two  molecules  of  hypochlorous  acid.  This 
may  explain  it : 

C120     +    H20     =     2HC10 
chlorine         water          hypochlo- 
monoxide  rous  acid 

It  cannot  be  separated,  but  its  salts  are  known,  and 
they  are  great  bleaching  agents.  The  reason  why  is 
because  it  gives  off  oxygen  so  easily.  Thus  potassium 
hypochlorite,  KC1O,  becomes  potassium  chloride,  KC1, 
plus  oxygen.  The  Cl  slips  around  the  O  to  get  at  its 
favorite,  K,  which  it  likes  better  than  O.  There  are  a 
number  of  other  combinations  of  chlorine  with  oxygen, 
all  of  them  acids,  and  there  is  always  the  likelihood  of 
the  oxygen  atoms  wandering  away  to  any  other  mate 
that  they  can  find.  A  neat  little  experiment  to  show 
this  is  to  mix  some  powdered  sugar  and  some  chlorate 

92 


THE    RED-HEADED    HALOGENS 

of  potash  together,  carefully,  and  then  add  a  drop  or 
two  of  concentrated  sulphuric  acid.  The  whole  mass 
will  immediately  burst  into  flame,  because  the  sul- 
phuric acid  will  drive  the  chlorine  dioxide  from  the 
chlorate  of  potash,  and  chlorine  dioxide  will  not  endure 
for  a  minute  if  there  is  anything  as  easy  to  oxidize  as 
sugar  at  hand.  Sugar  is  composed  of  carbon,  hydro- 
gen, and  a  little  oxygen. 

One  of  the  chief  uses  of  all  of  these  halogen  com- 
pounds with  oxygen  is  as  oxidizing  agents.  Oxygen 
does  not  seem  to  feel  comfortable  when  combined 
directly  with  a  halogen. 

The  greatest  use  of  chlorine  in  a  free  state  or  loosely 
combined  is  as  a  bleaching  agent.  The  way  it  works, 
theoretically,  is  that  one  molecule  (or  two  atoms)  of 
chlorine  gas  and  one  molecule  of  water  unite  to  form 
two  molecules  of  hydrochloric  acid  (HC1)  and  set 
free  one  atom  of  oxygen.  But  chlorine,  as  well  as 
hydrochloric  acid,  eats  into  and  disintegrates  fiber, 
so  that  laundries  which  use  this  easy  bleaching  agent 
have  become  the  bane  of  the  man  with  shirts  and  the 
distress  of  the  housewife  with  her  weekly  wash.  Wash- 
ing clothes  is  a  chemical  problem,  by  no  means  made 
perfect  as  yet,  although  progress  has  been  and  is 
being  continually  made.  What  bids  fair  to  be  an 
even  greater  use  is  in  the  disinfection  of  drinking- 
water.  Very  small  quantities  of  it  will  effectively 
destroy  bacterial  life  by  oxidation,  as  we  have  ex- 
plained, even  in  the  effluent  from  sewage. 

Now  that  the  electrolytic  method  of  producing  soda 
has  made  chlorine  plentiful,  and  since  it  is  easily 
liquefied  (by  cooling  and  compressing)  and  shipped  in 
convenient  cylinders,  there  is  no  more  excuse  for  the 
spread  of  epidemics  through  drinking-water.  A  little 
apparatus  in  the  gate-house  of  a  large  municipal 

93 


EVERYMAN'S    CHEMISTRY 

water-supply  will  effectively  chlorinate  every  bit  that 
is  used.  The  effluents  from  sewage-disposal  plants,  if 
treated  with  chlorine,  may  be  safely  allowed  to  flow 
into  rivers  without  fear  of  contaminating  the  water. 

In  his  work  on  Municipal  Chemistry,  Professor 
Baskerville  brought  out,  several  years  ago,  the  value 
that  minute  quantities  of  chlorine  would  have  if  added 
to  the  water  with  which  streets  are  flushed.  It  was 
later  urged  by  Albert  H.  Hooker  in  his  book  on 
Chloride  of  Lime  and  Sanitation.  Here  we  have  the 
greatest  disinfectant  known  to  man,  at  once  cheap 
and  available.  And  we  have  in  the  dust  of  our  streets 
the  bacilli  of  tuberculosis,  tetanus,  and  the  germs  that 
are  said  to  be  active  in  spreading  coughs  and  colds, 
besides  a  lot  more  of  the  kind.  But  so  far  as  I  know 
the  sprinkling  of  streets  of  a  city  with  chlorinated 
water  has  never  been  thoroughly  tried  out  yet. 

Bromine  is  used  in  medicines,  the  many  bromides 
having  the  effect  of  inducing  sleep.  Compounds  of 
bromine  also  are  availed  of  in  the  dyestuff  industry. 

Iodine  is  principally  used  in  medicine  and  also  in 
laboratories  as  a  reagent  in  analysis.  There  is  a  very 
large  quantity  of  it  contained  in  seaweed,  and  the  new 
potash  industry  of  the  Pacific  coast,  whereby  potash 
is  extracted  from  giant  seaweed  or  kelp,  will  probably 
be  glad  to  hear  of  a  good  process  whereby  iodine  may 
be  extracted  economically  as  a  by-product. 


IX 

SULPHUR,   SULPHURIC  ACID,  AND  SULPHUR  COMPOUNDS 

Sulphur's  Cousinship  with  Oxygen — Dr.  Jekyll  and  Mr.  Hyde — 
Herman  Frasch'.s  Clever  Device — A  Few  Sulphur  Combinations 
— Sulphur  Oxides — Sulphuric  Acid — The  Old  Horse  of  Chemistry 
— Its  Uses  and  How  it  is  Made — Chamber  and  Contact  Proc- 
esses— The  Chemical  Bank — Thiosulphates — Note  on  the  Ele- 
ment Selenium 

SULPHUR  is  related  to  oxygen  under  the  Periodic 
Law,  although  it  does  not  look  like  it  or  smell 
like  it  or  make  combinations  that  resemble  those  of 
oxygen  in  appearance;  it  is  only  when  we  consider 
them  chemically  that  we  note  the  cousinship.  We 
shall  touch  upon  these  resemblances  as  we  pass  them 
by. 

Sulphur,  like  certain  other  elements  that  we  shall 
consider  later,  displays  what  are  rather  awkwardly 
called  "allotropic  modifications."  We  have  spoken 
of  the  personal  quality  of  matter,  especially  within 
the  domain  of  catalysis,  and  here  we  have  another 
manifestation  that  indicates  how  like  persons  matter 
is.  Many  books  besides  Dr.  Jekyll  and  Mr.  Hyde 
have  been  written  about  the  phenomenon  of  dual  or 
multiple  personality  in  individuals.  Now  allotropy  is 
this  multiple  personality  in  elements.  We  recall  how 
oxygen  is  a  gas  of  the  air,  and  that  the  same  oxygen 
may  become  ozone.  The  same  holds  true  of  sulphur. 
It  may  be  crystalline,  and  as  such  it  crystallizes  into 

95 


EVERYMAN'S   CHEMISTRY 

two  forms.  It  occurs  in  an  amorphous  state  as  a 
powder,  and  as  a  liquid  it  has  two  forms — that  of  a 
mobile  liquid  and  that  of  a  viscid  one.  All  the  time  it 
is  sulphur,  chemically  pure  sulphur,  and  nothing  else. 
We  know  how  to  bring  these  changes  in  form  about, 
and  there  is  probably  some  regrouping  of  the  atoms 
in  the  molecules  which  causes  the  changes. 

Sulphur,  like  oxygen,  has  two  hooks  or  affinities  to 
combine  with  other  atoms;  but,  unlike  oxygen,  if  it 
needs  more  than  two  it  displays  four,  and  in  still 
other  combinations  it  avails  itself  of  six.  I  do  not 
know  of  any  relation  between  the  number  of  hooks  an 
element  shows  for  combining  and  its  allotropic  mod- 
ifications. 

Sulphur  is  found  in  volcanoes  and  in  direct  combina- 
tions with  metals  which  are  called  sulphides.  In 
Louisiana  and  Texas  there  are  enormous  deposits  of 
this  element  in  a  free  state  deep  under  the  quicksand, 
and  most  of  the  supply  for  the  United  States  comes 
from  this  source.  It  is  obtained  by  the  process  de- 
vised by  the  late  Herman  Frasch,  who  sank  through 
the  sand  a  six-inch,  a  three-inch,  and  a  one-inch  pipe, 
one  inside  of  the  other,  and  through  the  six-inch  pipe 
he  forced  water,  superheated  and  under  pressure  of 
one  hundred  pounds  per  square  inch.  Through  the 
three-inch  pipe  he  drove  hot,  compressed  air,  and  this, 
mingling  with  the  sulphur  which  the  superheated 
water  had  melted,  caused  it  to  flow  up  through  the 
one-inch  pipe.  A  screen  at  the  bottom  of  the  one- 
inch  pipe  keeps  the  earth  out,  and  very  pure  sulphur 
comes  up,  is  cast  in  tanks,  and  housed  in  great  blocks. 
In  Europe  the  chief  source  of  supply  is  Mount  Etna, 
in  Sicily,  and  it  is  also  found  in  extinct  volcanoes  in 
Japan. 

When  we  consider  that  sulphur  combines  with  other 

96 


SULPHUR 

elements  very  much  as  oxygen  does,  we  can  see  what 
a  vast  number  of  sulphur  compounds  are  possible. 
And  it  can  produce  more  different  kinds  of  evil-smell- 
ing combinations  than  any  other  element. 

Just  as  oxygen  and  hydrogen  combine  to  produce 
water,  H2O,  so  sulphur  and  hydrogen  combine  to 
produce  hydrogen  sulphide,  H2S,  which  is  a  gas  and 
smells  like  rotten  eggs. 

Sulphur  unites  with  the  halogens  somewhat  after 
the  manner  of  oxygen,  but  with  entirely  different  re- 
sults. There  is,  for  instance,  the  chloride,  S2C12,  which 
is  a  liquid  with  a  nasty  odor  and  has  the  capacity  to 
dissolve  sulphur.  The  bichloride,  SC12,  is  also  known, 
as  well  as  is  the  tetrachloride,  SC14,  and  there  are 
other  halogen  compounds. 

With  the  metals  it  unites  directly  to  form  sulphides, 
just  as  oxygen  forms  oxides.  Some  of  these  sulphides 
of  metals  are  the  crystalline  iron  pyrites,  copper  py- 
rites, cinnabar  (mercury  sulphide),  galenite  or  galena 
(lead  sulphide),  zinc-blende  (zinc  sulphide),  which  are 
well  known,  but  there  are  very  many  more  of  them. 
In  combination  with  iron,  as  the  amorphous  sulphide 
of  iron,  it  is  a  powder  without  any  mechanical  quali- 
ties. Sulphur  makes  iron  brittle  when  present  even 
in  very  small  quantities.  Coal  that  contains  too 
much  sulphur  ruins  boilers  and  grate-bars;  in  fact, 
sulphur  is  a  great  nuisance  in  fuel. 

With  carbon  it  combines  to  produce  carbon  bi- 
sulphide, CS2,  which  will  dissolve  sulphur  and  rubber 
and  which  in  the  impure  commercial  state  smells 
like  destruction.  One  whiff  of  it  is  enough  to  fix  it  in 
memory.  It  is  used  as  an  insecticide,  and  in  chemical 
industry  to  produce  carbon  tetrachloride,  in  the  pro- 
duction of  artificial  silk  and  for  other  purposes. 

It  is  with  oxygen,  however,  that  sulphur  forms  the 

97 


EVERYMAN'S   CHEMISTRY 

compounds  which  bring  it  into  most  frequent  com- 
mercial use.    There  are  four  of  them  known: 


Sulphur  sesquioxide 

Sulphur  dioxide  SO2 

Sulphur  trioxide  SO3 

Sulphur  heptoxide  82(1)7 

Of  these  we  shall  consider  only  two,  the  dioxide  and 
the  trioxide,  and  this  brings  us  to  the  consideration 
of  what  we  may  call  the  Old  Horse  of  Chemistry,  or 
sulphuric  acid. 

When  you  get  up  in  the  morning  and  turn  on  the 
water  for  your  bath,  you  use  a  nickel-plated  faucet 
which  required  sulphuric  acid  in  its  manufacture. 
Your  tub,  if  it  be  enameled,  has  met  sulphuric  acid 
before  it  became  what  it  is  ;  and  if  it  is  an  old-fashioned 
one  of  tin,  plated  on  sheet  copper,  it  needed  even  more 
sulphuric  acid  before  it  took  its  place  in  civilization 
as  a  bath-tub.  The  water  in  which  you  bathe  has 
probably  been  treated  with  sulphate  of  copper  to 
clear  it  of  algae.  The  towel  with  which  you  dry  your- 
self has  met  sulphuric  acid  before  you  bought  it,  and 
the  soap-maker  possibly  found  it  necessary  to  use 
some  in  the  preparation  of  your  soap.  The  bristles  of 
your  hair-brush  have  been  treated  with  it,  and  the 
back  of  your  brush,  as  well  as  your  comb,  if  they  be 
of  celluloid,  could  not  be  produced  without  it.  Your 
razor,  before  it  reached  its  present  high  estate,  may 
have  been  pickled  in  sulphuric  acid  after  it  was  an- 
nealed. 

As  you  put  on  your  underwear  you  may  recall  that 
the  bleacher  and  the  dyer  used  sulphuric  acid  on  the 
thread  before  it  was  knit  or  woven,  or  upon  the  fabric 
afterward.  As  you  button  up  your  outer  garments 
you  may  be  reminded  also  that  sulphuric  acid  was 

98 


SULPHUR 

needed  in  scouring  the  wool,  in  making  the  dye,  and 
in  the  process  of  dyeing  the  cloth. 

The  button-maker  needed  some  before  your  buttons 
were  complete.  The  tanner  needed  some  in  making 
the  leather  for  your  shoes,  and  it  is  also  used  to  pro- 
duce shoe-polish.  The  cushion  upon  which  you  may 
rest  your  pious  knees  in  your  devotions  has  met 
sulphuric  acid  in  one  way  or  another  more  than  once 
before  it  reached  its  present  dignity. 

At  breakfast  your  cup  and  saucer  may  have  come 
into  being  without  the  aid  of  sulphuric  acid,  but  only 
provided  they  are  plain  white.  To  produce  the  con- 
stituents of  aqua  regia,  which  dissolved  the  gold  for 
gilt  ornamentation,  sulphuric  acid  was  used.  The 
silver  of  which  your  spoon,  knife,  and  fork  are  made 
may  come  from  a  smelter  which  has  first  burned  the 
sulphurous  ore  and  made  sulphuric  acid  of  the  fumes, 
while  if  they  are  silver-plated,  they  were  plated  in  a 
sulphuric-acid  bath.  The  farmer  who  raised  the 
wheat  of  which  your  rolls  are  made  probably  used 
acid  phosphate  on  his  land  to  encourage  the  wheat 
to  grow.  Acid  phosphate  is  phosphate  rock  treated 
with  sulphuric  acid.  The  paper-maker  needed  some 
sulphonated  aniline  blue  to  tint  your  morning  paper, 
even  if  he  used  no  sulphite  pulp,  and  it  would  be  a 
rare  ink  that  is  innocent  of  the  touch  of  sulphuric  acid 
at  some  point  in  its  history. 

If  you  eat  buckwheat-cakes  and  syrup,  the  syrup 
needed  it,  and  as  for  your  artificial  light,  if  you  get 
up  early  enough  to  need  it,  you  would  be  driven 
back  to  candles  if  it  were  not  for  this  product. 
It  is  needed  in  the  refining  of  kerosene  and  gas- 
olene, and  as  for  your  electric  light,  brought  to 
you  by  currents  of  electricity  through  copper  wires 
— where  would  the  electric-light  industry  be  with- 

99 


EVERYMAN'S   CHEMISTRY 

out  copper?  And  where  would  the  copper  industry 
be  without  the  electrolytic  process  of  refining,  which 
requires  enormous  quantities  of  sulphuric  acid?  It 
would  be  paralyzed. 

We  have  heard  of  the  embarrassment  of  industry 
by  the  lack  of  German  dyes,  but  that  is  a  mere  baga- 
telle compared  with  the  general  break-up  that  would 
follow  a  dearth  of  sulphuric  acid.  We  can  neither  go 
to  war  and  have  smokeless  powder  nor  can  we  live  in 
peace  without  it.  Wherever  you  go  in  civilization  you 
cannot  get  out  of  its  path.  You  may  never  see  it,  you 
may  not  know  its  qualities  and  its  very  remarkable 
chemical  personality,  and  you  had  better  not  touch 
it,  but  almost  invariably  it  has  been  around  before 
you. 

All  of  this  will  explain  but  a  fraction  of  the  all- 
pervasive  ubiquity  of  sulphuric  acid  in  the  arts  of 
what  we  call  civilization.  And  its  use  is  growing  along 
with  the  development  of  chemical  industry  and  the 
science  of  agriculture. 

It  has  been  known  as  a  commercial  product  in 
the  United  States  since  1793.  The  first  step  in  the 
process  of  making  it  is  to  burn  sulphur.  When  you 
burn  sulphur  you  produce  a  gas  containing  one  atom 
of  sulphur  to  two  of  oxygen  in  the  molecule.  Every- 
body knows  the  choking  smell  of  this  gas;  you  used 
to  produce  it  every  time  you  lighted  an  old-fashioned 
sulphur  match.  It  is  easy  enough  to  produce  it  on 
a  small  scale,  but  when  it  comes  to  doing  this  very 
thing  on  a  large  scale,  and  measuring  the  units  by 
the  ton,  it  will  be  seen  that  even  here  there  are  engi- 
neering problems  involved  that  are  far  from  easy. 
And  we  haven't  sulphuric  acid  yet,  by  long  odds. 
We  have  with  our  two  atoms  of  oxygen  to  one  of 
sulphur  the  anhydrid  of  sulphurous  acid,  the  first 

100 


SULPHURIC   ACLE) 

step  in  the  process :  what  we  are  after  is  the  anhydrid 
of  sulphuric  acid;  we  must  worry  -another"  a^cjmi&f 
oxygen  into  that  molecule  and  make  SO3  instead  of 
SO2.  If  we  leave  it  by  itself  an  indefinite  time  and 
allow  plenty  of  air  to  weaken  it,  it  will  change  over 
as  we  want  it  to,  but  we  never  could  make  a  com- 
mercial product  that  way.  No,  we  must  introduce  an 
oxygen-carrier  into  the  chamber  that  contains  the 
gaseous  product  of  our  first  step — something  that 
will  not  only  give  up  an  atom  of  oxygen,  but  find  a 
taker  in  each  molecule  of  SO2.  Oxides  of  nitrogen 
will  do  this,  and  then  get  back  the  oxygen  they  have 
lost  from  the  air,  so  that  they  may  be  used  over  again 
and  again  with  very  slight  loss.  That  is  the  way  we 
get  our  SO3  in  the  old  chamber  process  which  we  shall 
now  describe. 

As  the  first  step,  either  sulphur  is  burned  or  the 
sulphurous  ore  is  roasted  and  the  fumes  of  SO2  are 
passed  first  through  a  dust-flue  and  then  through  what 
is  called  a  Glover  tower,  the  purpose  of  which  is  to 
get  a  thorough  mixture  of  the  gases  wanted.  This  is 
a  tower  filled  with  lumps  of  inert  material,  and  there 
trickles  down  through  the  tower  sulphuric  acid  con- 
taining oxides  of  nitrogen  which  are  dissolved  in  it. 
The  sulphurous  fumes  ascend  against  this  stream, 
carry  along  the  oxides  of  nitrogen,  and  proceed  into 
great  leaden  chambers.  Steam  is  blown  into  the 
chambers  at  various  points^  Here  a  complicated  re- 
action takes  place,  but  in  effect  nitric  oxide,  NO, 
unites  with  the  oxygen  of  the  air  to  form  nitrogen 
peroxide,  NO2.  Then — 

SO2     +    NO2     +    H2O  =     H2SO4     +  NO 

sulphur      nitrogen       water        sulphuric  nitric 

dioxide      peroxide  acid  oxide 

101 


EVERYMAN'S    CHEMISTRY 

and  then,,  again— 

2ND     +    O2     =     2NO2 
nitric        oxygen      nitrogen 
oxide         (from       peroxide 
air) 

and  the  cycle  is  complete.  So  we  have  sulphuric  acid 
on  the  floor  of  the  chambers,  and  the  gaseous  oxides 
of  nitrogen,  which  must  not  be  lost,  mixed  with  air. 
From  the  last  chamber  the  gases  are  led  into  a  tall 
Gay-Lussac  tower,  filled  with  coke,  and  over  which, 
from  the  top  downward,  there  trickles  concentrated 
(78  per  cent.)  sulphuric  acid.  This  dissolves  the 
oxides  of  nitrogen,  but  not  the  air,  which  passes 
out  through  the  stack.  The  concentrated  acid  with 
the  oxides  of  nitrogen  dissolved  in  it  is  then  pumped 
over  from  the  bottom  of  the  Gay-Lussac  tower  to  the 
top  of  the  Glover  tower,  where  it  proceeds  to  give  up 
the  oxides  that  it  has  in  solution,  just  as  described 
above,  and  this  process  goes  on  over  and  over  again. 
The  sulphuric  acid  taken  from  the  chambers  is  of 
about  65  per  cent,  strength,  and  this  is  usually 
concentrated  by  boiling  off  the  water  in  pans  made  of 
a  very  high  silicon  iron. 

There  is  no  such  trouble  in  getting  water  attached 
to  the  SO3  molecule  as  we  had  in  getting  that  extra 
atom  of  oxygen  into  it.  The  trouble  is  to  keep  the 
water  away.  The  acid  that  comes  out  of  the  leaden 
chambers  is  strong  enough  for  use  in  some  industries 
(for  instance,  to  produce  acid  phosphate  for  fertilizers) , 
but  it  is  not  strong  enough  for  general  commercial 
purposes.  Not  all  the  water  is  boiled  off  in  the  con- 
centrating -  pans ;  you  cannot  produce  a  100  per 
cent.  H2SO4  by  this  concentrating  process,  but  it  is 
made  strong  enough  for  a  great  many  purposes — for 
most  purposes,  in  fact. 

102 


SULPHURIC   ACID 

Dilute  sulphuric  acid  must  not  be  shipped  in  iron 
containers  because  it  will  eat  right  through  the  iron, 
whereas  strong  sulphuric  acid  may  be  hipped  in  tank- 
cars  if  the  necessary  precautions  are  taken  to  keep 
water  out.  This,  according  to  a  plausible  theory, 
is  because  the  salts  of  iron,  produced  by  the  action 
of  the  acid  upon  the  iron  walls  that  contain  it,  are 
very  soluble  in  water,  but  insoluble  in  strong  sulphuric 
acid,  and  thus  make  a  protective  coating  to  the  inside 
of  the  walls  which  cease  to  be  protective  as  soon  as  the 
solvent  water  is  introduced. 

The  contact  process  is  an  achievement  in  catalysis 
and  is  a  development  of  the  last  twelve  or  fifteen  years, 
so  far  as  practice  is  concerned.  It  consists  in  inducing 
the  sulphurous  fumes  (SO2)  to  unite  with  oxygen  of 
the  air  and  form  SO3  in  the  presence  of  one  or  more 
catalysts.  The  pyrites  are  roasted,  and  the  cinder, 
consisting  chiefly  of  iron  oxides,  but  also  some  oxides 
of  copper,  arsenic,  and  other  metals,  are  used  as  the 
first  step  in  which  about  one-half  of  the  SO2  (mixed 
with  air)  is  converted  to  SOs.  This  is  a  black,  dirty 
gas,  mixed  SO2,  S03,  CO2,  02,  and  N2.  From  this 
point  it  is  cooled  and  cleaned  and  scrubbed  according 
to  the  process  employed  and  the  conditions  at  hand, 
until  a  gas  of  remarkable  freedom  from  foreign  mat- 
ter is  obtained.  This  is  especially  necessary  be- 
cause the  remaining  half  of  the  SO2  is  still  to  be  con- 
verted to  SO3,  and  the  slightest  amount  of  arsenic  or 
any  of  a  number  of  foreign  substances  or  dust  will 
" poison"  the  catalyst  so  that  it  will  not  do  its  work. 
So  far  is  this  purification  carried  that  among  the  great- 
est producers  the  gas  will  stand  the  Tyndall  test; 
that  is,  that  a  beam  of  very  concentrated  light  passed 
through  a  dark  chamber  containing  it  will  not  show 
a  particle  of  dust.  When  we  think  of  the  myriads  of 
8  103 


EVERYMAN'S   CHEMISTRY 

dust  particles  we  see  if  a  beam  of  ordinary  daylight 
is  let  into  any  living-room  that  is  darkened,  we  can 
imagine  how  well  this  work  of  purification  has  been 
done.  The  gases  are  then  passed  over  devices  con- 
taining platinized  asbestos,  and  by  the  time  this 
process  is  completed  practically  all  the  SO2  is  con- 
verted to  SO3.  From  this  point  the  process  is  very 
like  the  old  one;  the  SO3  is  caught  up  by  strong  sul- 
phuric acid,  which  not  only  absorbs  SO3  until  it  be- 
comes 100  per  cent.  H2SO4,  but  100  per  cent,  sulphuric 
acid  will  also  dissolve  the  anhydrid. 

Let  us  get  this  a  little  clearer.  SO3,  you  recall, 
is  the  anhydrid  which  with  water,  H2O,  produces  the 
acid  H2SO4.  If  you  have  an  acid  that  is  90  per  cent, 
sulphuric  acid  and  10  per  cent,  water,  then,  as  SO3 
is  added  to  it,  the  acid  will  gradually  become  100 
per  cent,  sulphuric  acid.  As  soon  as  this  stage  is 
passed  and  we  have  what  is  known  as  free  anhydrid 
dissolved  in  the  sulphuric  acid,  it  is  called  oleum. 
This  is  likely  to  have  about  20  per  cent,  free  anhydrid. 
If  the  anhydrid  only  is  wanted — i.e.,  the  fuming,  solid 
S03,  without  any  H2SO4  in  it — the  SO3  is  usually  dis- 
tilled off  from  the  oleum  by  gentle  heating. 

Some  claim  that  the  contact  process  will  in  time 
supplant  the  chamber  process,  and  I  think  it  likely, 
in  the  course  of  a  pretty  long  time.  The  reason  is 
that,  under  ideal  conditions  and  flawless  management, 
it  should  cost  no  more  to  make,  say,  97  per  cent, 
sulphuric  acid  by  the  contact  process  than  65  per 
cent,  chamber  acid.  But  it  takes  years  to  achieve 
a  very  high  degree  of  administrative  efficiency,  and 
the  process  is  more  delicate,  and  there  are  patents 
covering  all  sorts  of  steps  in  it,  and  royalties  must  be 
paid — and  the  chamber  process  is  easy.  I  think  the 
chamber  process  will  still  be  in  operation  when  many 

104 


SULPHURIC   ACID 

of  the  young  fellows  of  to-day  will  be  referred  to  as 
graybeards. 

Lately  the  United  States  Department  of  Agriculture 
has  proposed  still  another  method  that  is  similar  to 
the  old  one,  except  that  instead  of  great  leaden  cham- 
bers for  the  reaction,  it  is  proposed  to  use  coils  of 
lead  pipe.  The  laboratory  tests  are  promising,  but 
no  large-scale  tests  have  been  made,  and  the  propor- 
tion of  surface  to  volume  is  so  different  in  laboratory 
.tests  from  that  in  practice  that  a  great  deal  must  be 
done  before  it  is  known  what  value,  if  any,  the  pro- 
posed method  has. 

This  heavy,  oily  fluid,  also  known  as  oil  of  vitriol, 
that  destroys  nearly  everything  with  which  it  comes 
in  contact,  is  like  fire  or  water  or  electricity — a  good 
servant  but  a  bad  master.  And  yet  it  is  about  the 
safest  and  most  biddable  chemical  we  know,  consid- 
ering its  strength.  And  in  its  strength  is  its  greatest 
usefulness.  We  do  not  employ  a  Percheron  stallion 
to  draw  a  baby-carriage,  and  yet  the  Percheron 
stallion  is  just  what  we  do  want  for  a  heavy  load  on 
a  bad  road.  Now  sulphuric  acid  is  one  of  the  great 
dray-horses  of  chemistry.  But  if  we  carry  the  equine 
simile  any  further  we  shall  get  into  difficulties,  for 
the  main  business  of  sulphuric  acid  is  to  bite  into  things 
chemically  and  play  hobs  generally,  under  control. 
All  of  its  get,  its  progeny,  its  colts,  or,  more  properly 
speaking,  the  sulphates  and  sulpho-conjugations,  are 
not  soluble  in  water,  but  so  many  of  them  are  that  it 
is  fair  to  say  that  one  of  the  principal  lines  of  business 
of  this  chemical  is  to  make  things  over  so  that  they 
will  dissolve  in  water.  Phosphate  rock  is  thus  made 
more  available  in  practice  for  the  soil.  Being  an  acid, 
it  will  neutralize  alkali,  and  a  new  use  for  great  quan- 
tities of  acid  produced  from  smelter  fumes  in  the 

105 


EVERYMAN'S   CHEMISTRY 

West  has  lately  been  proposed  in  the  reclamation  of 
alkali  deserts. 

The  founders  of  the  Chemical  National  Bank  of 
New  York  many  years  ago  started  in  business  making 
sulphuric  acid.  In  those  days  it  was  made  according 
to  a  "formula"  or  recipe:  burn  so  much  sulphur, 
and  do  thus  and  so  according  to  rule  and  gather  in 
your  product.  There  were  difficulties  of  transporta- 
tion and  in  manufacture  because  sometimes  the  cham- 
bers would  become  sick  and  not  perform  their  allotted 
tasks,  while  the  demand  for  the  product  was  irregular 
and  slight.  So  the  proprietors  closed  out  their  busi- 
ness, and,  having  a  charter  bounded  hardly  short  of 
their  imagination,  they  started  a  bank.  Now  the 
career  of  that  bank  has  been  so  honorable,  so  useful, 
and  so  distinguished  for  sound  business  methods  that 
we  are  bound  to  rejoice  that  the  Chemical  Bank 
was  duly  started.  But  those  interested  in  chemical 
industry  cannot  wholly  free  themselves  from  the 
wish  that  the  same  talent  for  organization  and  the 
same  high  character  which  qualified  those  men  for 
banking  might  have  remained  to  help  along  the 
chemical  industry  in  this  country  in  the  days  of  its 
struggles.  We  might  have  been  further  ahead  than 
we  are  now. 

I  have  intimated  that  sulphuric  acid  is  the  old 
horse  of  chemistry.  Then  soda  would  be  the  old 
mare.  And  there  is  lime.  Lime,  let  us  say,  is  the 
mule,  which  carries  off  great  loads  of  waste. 

Before  we  give  up  the  subject  we  must  consider  a 
little  trick  that  sulphur  has  in  working  its  way  into 
molecules,  very  like  the  way  of  oxygen  in  oxidation. 
For  instance,  a  sulphurous  acid  salt,  if  left  in  the  air 
long  enough,  will  go  over,  by  oxidation,  into  a  sul- 
phuric acid  salt: 

1 06 


SULPHUR    COMPOUNDS 

2Na2SO3     +    02     =     2Na2SO4 
sodium  oxy-  sodium 

sulphite  gen  sulphate 

Now,  if  we  digest  sodium  sulphite  with  finely  di- 
vided sulphur  for  some  time,  the  sulphur  will  work 
its  way  into  the  molecule  in  the  same  way,  and  we 
have: 


Na2S03     +     S     = 

sodium          sul-  sodium 

sulphite         phur     thiosulphate 

There  are  other  ways  of  doing  this,  but  we  shall 
not  discuss  them.  The  point  is,  we  have  what  the 
name  implies,  a  sulpho-sulphate,  because  the  prefix 
thio  is  taken  from  the  Greek  word  Oelov  (theion), 
which  means  sulphur.  Thiosulphuric  acid  is  not 
known  in  a  free  state,  but  we  have  its  salts.  The 
sodium  thiosulphate  is  called  by  photographers  hypo- 
sulphite of  soda,  or  ''hypo,"  and  is  used  to  dissolve 
the  chloride  or  bromide  of  silver  from  those  places  on 
the  photographic  plate  where  it  is  not  wanted.  We 
shall  see  how  useful  it  is  when  we  consider  pho- 
tography. It  forms  a  soluble  silver  sodium  thiosulphate 
as  follows  : 


AgCl     -f     NazSaOs     =  NaCl     + 

silver             sodium  common      silver  sodium 

chloride      thiosulphate  salt            thiosulphate 
or  "hypo" 

The  element  selenium  is  very  like  sulphur  in  its 
reactions.  It  is  also,  like  sulphur,  known  in  various 
forms  or  modifications.  It  is  a  brick-red  powder,  a 
black,  brittle,  glassy  mass,  a  red  crystalline  form,  and 
a  gray  metal.  It  is  sometimes  found  in  the  deposits 
of  Glover  towers  and  chambers  of  sulphuric  acid 

107 


EVERYMAN'S   CHEMISTRY 

works,  and  it  has  been  found  in  meteoric  iron.  Its 
chief  claim  to  fame  is  that  in  the  metallic  form  it 
conducts  electricity  very  much  better  in  the  light  than 
it  will  in  the  dark.  This  has  led  to  numerous  inven- 
tions and  some  curious  apparatus,  among  others  the 
''electric  dog"  of  J.  H.  Hammond,  Jr.,  of  Gloucester, 
Massachusetts.  A  little  four  -  wheeled  wagon  is 
equipped  with  a  chemical  battery,  and  selenium  re- 
sistance coils  are  placed  back  of  glass  lights  which 
are  supposed  to  represent  eyes.  If  a  strong  light  is 
thrown  upon  them,  this  turns  the  selenium  resistance 
coils  into  a  conductor,  and  the  "dog"  speeds  forward 
and  follows  the  light,  being  propelled  by  a  storage 
battery  which  it  contains.  The  light  causes  the 
selenium  coils  to  conduct  the  current  from  the  bat- 
tery to  the  motor. 

The  commercial  supply  of  selenium  is  obtained  from 
the  electrolytic  copper  refineries.  The  present  Amer- 
ican production  is  about  thirty  thousand  pounds  per 
annum.  Elementary  selenium  is  most  largely  used 
to  give  a  red  color  to  glass  (for  railroad  signal-lights, 
etc.),  and  it  is  also  employed  to  overcome  the  green 
color  of  glass.  Selenite  of  soda  is  used  to  impart  a 
bright  red  color  to  enamels.  Selenium  is  also  used  to 
a  limited  extent  in  medicine  and  bacteriology. 


X 


PHOSPHORUS,   ARSENIC,    ANTIMONY,    AND   BISMUTH 

Phases  of  Each — Relations  to  Nitrogen — Phosphorus  Fertilizers — 
Matches — A  Real  Triumph  in  Manufacturing — The  Ironmaster's 
Torment,  and  Why  He  Swears — Fish-bones  for  Brain  Food — 
The  Unaggressive  but  Poisonous  Arsenic — Its  Uses — Antimony 
and  Its  Trick  of  Expanding — Use  in  Type-metal  and  in  Alloys — 
Bismuth 

PHOSPHORUS  belongs  to  the  same  group  as 
1  nitrogen.  It  is  not  found  in  a  free  state  in 
nature  because  of  its  marked  affinity  for  oxygen.  It 
has,  like  nitrogen,  sometimes  three  hooks  and  some- 
times five,  according  to  its  pleasure.  When  driven 
out  of  combination  it  is  a  heavy,  crystalline  solid, 
yellowish  in  color,  and  it  melts  at  44°  and  boils  at 
290°  centigrade.  In  this  form  it  is  a  rank  poison. 
But  if  we  heat  it  in  a  closed  vessel  it  turns  into  a 
reddish  brown  powder  which  is  stable  and  inert  and 
has  little  poisonous  action,  because  of  the  difficulty  of 
absorption.  There  is  an  intermediate  scarlet  phos- 
phorus, and  yet  another  violet  or  black  modification, 
all  chemically  pure  phosphorus,  but  constituting  allo- 
tropic  modifications,  such  as  we  observed  in  sulphur, 
and  showing  different  phases  of  the  same  substance. 
Phosphorus  combines  with  hydrogen  to  produce 
phosphine,  PH3,  just  as  nitrogen  produces  ammonia, 
NH3.  Phosphine  is  a  very  poisonous  gas  and  has  a 
disagreeable  odor,  something  like  spoiled  fish.  Just 

109 


EVERYMAN'S    CHEMISTRY 

as  ammonia,  NH3,  dissolved  in  water,  H2O,  produces 
ammonium  hydroxide,  NH4OH,  which  is  known  only 
by  its  salts,  so  we  get  with  phosphine,  PH3,  in  water, 
H2O,  phosphonium,  PH4OH,  which  is  also  known 
only  in  its  salts;  that  is,  no  one  has  ever  succeeded 
in  producing  by  itself  either  ammonium,  NH4OH,  or 
phosphonium,  PH4OH,  although  there  are  plenty 
of  salts  in  which  an  acid  radical  takes  the  place 
of  the  OH.  Phosphonium  is  not  so  strongly  alkaline 
as  ammonium. 

Then  there  is  a  metaphosphoric  acid,  HPO3,  just 
like  nitric  acid,  HNO3,  but  an  entirely  different  prod- 
uct, and  by  no  means  so  strong  an  acid.  A  more  im- 
portant compound  with  oxygen  is  known  as  phos- 
phorus pentoxide,  P2O5,  which  is  a  white,  voluminous, 
snow-like  mass,  which  takes  up  water  to  produce  ortho- 
phosphoric,  or,  as  it  is  generally  called,  phosphoric  acid, 
H3PO4.  This  pentoxide  is  the  most  powerful  dryer 
known.  It  will  absorb  water,  if  present  in  sufficient 
quantity,  down  to  one  milligram  of  water  in  forty 
thousand  liters  of  air. 

About  one-tenth  of  i  per  cent,  of  good  soil  is 
phosphate,  and  plants  need  it.  So  do  animals.  As 
plants  exhaust  it  from  the  soil  it  needs  to  be  replaced, 
and  from  this  requirement  comes  the  great  phosphate 
fertilizer  industry.  The  effect  of  phosphates  upon 
plant  growth  seems  to  be  to  increase  the  prolificacy 
and  to  hasten  the  maturity  of  the  crops.  The  exact 
r61e  that  it  plays  is  still  rather  vague,  but  its  effect  is 
seen  in  increased  crops.  There  are  in  the  United 
States  vast  deposits  of  minerals,  chiefly  in  the  form  of 
various  phosphates  of  calcium.  They  are  found  in 
South  Carolina,  in  Florida,  in  Kentucky,  Wyoming, 
and  elsewhere.  This  country  is  very  rich  in  phosphate 
rock  and  exports  vast  quantities  of  it  to  Europe  in 

no 


PHOSPHORUS 

normal  times.  To  prepare  it  for  fertilizer  the  rock  is 
ground  fine  and  treated  with  about  an  equal  weight  of 
sulphuric  acid.  The  product  is  called  "acid  phos- 
phate** in  the  fertilizer  industry  and  is  applied  to  re- 
new the  phosphorus  taken  from  the  soil  by  plants. 
We  have  had  the  curious  situation  in  this  country  of 
the  manufacturers  of  acid  phosphate  urging  the  farmer 
to  buy  their  product  as  the  thing  most  needful,  the 
German  Kali  Syndicate  urging  potash  upon  the  farmer 
as  that  for  which  his  plants  do  most  ravenously  hun- 
ger, and  the  Chilean  nitrate  people  pressing  upon 
the  bewildered  husbandman  his  need  of  fixed  nitrogen. 
That  situation  has  improved  somewhat,  and  at  the 
time  of  the  present  writing,  when  there  is  a 
potash  famine  in  the  land,  it  is  doubtful  if  very  much 
phosphate  or  nitrate  is  offered  as  a  substitute  for 
potash.  The  mining  and  sale  of  phosphate  rock  is 
one  of  the  great  industries  of  the  United  States. 

The  old-fashioned  sulphur  matches  were  made  by 
dipping  the  sticks  first  into  molten  sulphur  and  then 
the  tips  into  a  paste  containing  yellow  phosphorus, 
an  oxidizing  agent  and  a  gum  to  protect  the  phos- 
phorus from  the  air  and  to  keep  the  mass  together. 
Enough  heat  was  generated  by  rubbing  the  tip  against 
any  rough  surface  to  start  the  reaction  between  the 
phosphorus  and  the  oxidizing  agent  (manganese  di- 
oxide, for  instance),  and  that  in  turn  set  fire  to  the 
sulphur,  which  ignited  the  wood.  But  not  only  was 
the  fire  danger  of  these  matches  very  great:  the  yel- 
low phosphorus  is  a  nasty  poison ;  the  men  who  worked 
in  the  industry  got  "phossy  jaw,"  and  died  of  it,  and 
now  the  manufacture  of  such  matches  is  forbidden 
by  law.  The  new  kind  of  "strike  anywhere"  matches 
have  a  tip  of  phosphorus  sesquisulphide  in  place  of 
the  yellow  phosphorus.  From  the  structure  of  these 

in 


EVERYMAN'S   CHEMISTRY 

matches,  with  the  ignition  surface  spreading  over  the 
tip  of  the  match  instead  of  enveloping  the  end,  the 
fire  hazard  is  lessened. 

Safety  matches  are  made  of  potassium  chlorate, 
powdered  glass,  rosin,  glue,  and  coloring  matter,  with 
red  or  amorphous  phosphorus  on  the  sides  of  the  box. 
It  is  a  pleasure  to  record  that  the  manufacture  of 
matches,  involving  as  it  does  the  use  of  phosphorus, 
has  changed  entirely  so  far  as  it  has  come  within  the 
hands  of  certain  great  administrators.  It  is  not  many 
years  ago  that  to  work  in  a  match-factory  was  a  job 
that  any  man  might  dread.  Phosphorus  is  a  nasty 
poison,  and  its  effects  are  cumulative  and  cruel.  By 
the  substitution  of  the  sesquisulphide  for  elemental 
phosphorus  the  hazard  to  health  and  life  is  removed, 
and  one  large  manufacturing  company,  having  useful 
patents  covering  the  process,  presented  its  patents 
to  the  United  States  Government,  so  that  any  manu- 
facturer of  matches  may  use  them.  The  health  record 
of  the  company's  own  works  is  something  to  be  proud 
of,  and  it  enjoys  the  advantage  of  well-paid,  satisfied, 
and  loyal  employees. 

Rocks  containing  phosphates  of  calcium  and  phos- 
phorus in  other  forms  are  very  wide-spread  and  are 
often  found  where  they  are  not  wanted.  For  instance, 
when  they  are  found  mixed  in  with  iron  ores  the  iron- 
master is  likely  to  become  unfit  as  a  member  of 
society.  You  cannot  make  steel  by  the  old  Bessemer 
process  unless  the  amount  of  phosphorus  present  is 
very  slight,  because  phosphorus  spoils  the  steel.  In 
the  open-hearth  process  more  phosphorus  can  be  al- 
lowed, as  in  this  way  it  is  boiled  off.  But  generally 
speaking,  phosphorus  is  to  the  metals  as  whisky  is 
to  man.  It  has  its  uses,  but  it  can  do  all  sorts  of 
harm.  A  little  phosphorus  in  iron  or  steel  will  make 

112 


ARSENIC 

it  crystallize,  and  so  it  becomes  brittle  and  generally 
unreliable.  On  the  other  hand,  it  is  useful  in  certain 
alloys.  Phosphor  bronze,  for  instance,  is  an  alloy  of 
phosphorus,  copper,  and  tin.  It  is  very  hard  and  firm, 
and  is  used  in  making  axle  bearings.  But  there  is 
much  more  effort  made  to  get  phosphorus  out  of  metals 
than  there  is  to  get  it  in. 

There  used  to  be  a  tradition  to  the  effect  that  phos- 
phorus was  food  for  the  mind,  because  there  is  a 
slight  amount  of  it  found  in  the  brain.  It  was  held 
that  a  diet  of  fish  was  especially  to  be  recommended 
because  phosphorus  is  also  found  in  fish,  and  therefore 
that  the  aspirant  after  intellectual  life  should  address 
himself  to  codfish,  shad,  and  even  bullheads  and  suck- 
ers. The  element  is  indeed  found  in  fish,  but  chiefly 
as  calcium  phosphate  in  their  bones. 

Arsenic  behaves  something  like  phosphorus  in  its 
reactions.  Usually  it  has  three  hooks,  but  sometimes 
it  has  five,  and  it  shows  several  allotropic  modifica- 
tions. It  may  appear  as  a  gray,  crystalline  substance, 
and  a  good  conductor  of  electricity,  or  it  may  take  the 
form  of  yellow  crystals,  or  of  a  gray,  amorphous  pow- 
der or  a  black  powder.  It  combines  with  oxygen  to 
produce  oxides,  and  these  with  water  form  acids.  With 
the  halogens  it  combines  every  way  possible,  and 
nearly  all  of  its  combinations  are  poisonous.  So  is 
pure  arsenic. 

With  hydrogen  it  forms  two  combinations,  the  im- 
portant one  of  which  is  arsine,  AsH3.  It  is  a  gas,  and 
smells  like  garlic,  but  no  one  is  able  to  smell  it  in 
quantity  for  any  length  of  time,  for  the  very  good 
reason  that  it  is  one  of  the  rankest  poisons  there  are, 
nearly  as  dangerous  as  prussic  acid. 

Arsenic  is  found  in  nature  in  a  free  state,  as  an  oxide 

113 


EVERYMAN'S    CHEMISTRY 

or  ''white  arsenic,"  and  in  direct  combination  with 
metals  as  arsenides.  From  a  chemical  standpoint  it 
is  not  very  aggressive,  and  it  would  seem  that  its 
poisonous  quality  must  be  due  to  catalysis.  It  is 
found  in  slight  quantity  in  many  ores,  but  is  usually 
distilled  or  sublimated  off  in  the  process  of  smelting. 

Of  its  two  compounds  with  oxygen,  arsenious  oxide, 
As2O3,  or  white  arsenic,  is  the  best  known.  It  is  used 
in  glass-making  to  remove  the  color  produced  by  the 
lower  oxides  of  iron.  It  is  also  used  in  enameling,  in 
calico-printing,  for  fireworks,  to  prevent  boiler  scale, 
for  fly  and  rat  poisons,  and  as  a  preservative  for 
mounted  birds  and  animals.  Paris  green  is  arsenite  of 
copper  (CuHAsOa),  and  is  a  beautiful  green  pigment 
that  was  at  one  time  in  popular  use  as  a  paint, 
for  coloring  wall-paper,  etc.,  but  it  is  such  a  vicious 
poison  that  its  use  is  generally  restricted  in  this  re- 
spect. Farmers  find  it  useful  for  killing  potato-bugs. 
Arsenic  in  one  form  or  another  has  long  been  a  favorite 
medium  of  the  poisoners,  although  the  tests  to  detect 
it  are  among  the  most  delicate  known,  the  presence 
of  the  most  minute  quantities  being  capable  of  demon- 
stration. So  delicate  is  one  test  that  sometimes  the 
slight  amount  contained  in  the  glass  has  been  partially 
dissolved  out  during  the  analysis,  and  dire  confusion 
has  resulted.  The  careful  analyst  tests  his  apparatus 
for  arsenic  first. 

As  with  many  other  poisons,  one  may  grow  accus- 
tomed to  taking  arsenic  in  increasing  amounts  until 
more  than  double  an  ordinary  fatal  dose  is  taken  with 
impunity.  The  inhabitants  of  Styria  eat  it  (white 
arsenic)  to  increase  their  endurance.  They  are  said 
to  be  of  fresh  complexion  and  long-lived,  but  to  die 
suddenly.  It  is  occasionally  given  to  horses  in  small 
quantities  to  improve  the  appearance  of  their  coats, 

114 


ANTIMONY 

especially  when  a  sale  to  some  one  living  at  a  good 
distance  away  is  anticipated. 

In  alloys  with  metals  arsenic  has  a  tendency  to 
make  them  brittle. 

Antimony  belongs  to  the  same  group  as  arsenic, 
phosphorus,  and  nitrogen;  it  has  sometimes  three 
hooks  and  sometimes  five ;  it  has  three  allotropic  modi- 
fications— it  appears  as  a  crystalline,  silvery-white, 
brittle,  metallic  substance,  and  as  a  yellow,  and  as  a 
gray  powder.  The  last  is  known  as  "explosive  anti- 
mony," and  when  heated  or  struck  or  scratched  it 
changes  into  the  crystalline  form,  increasing  in  density 
and  with  great  heat. 

It  is  found  in  small  quantities  in  a  free  state  in 
nature,  but  usually  as  an  oxide  or  in  combination 
with  sulphur,  arsenic,  and  the  metals.  The  most 
common  form  is  the  sulphide,  called  stibnite,  Sb2Ss. 

It  makes,  in  a  general  way,  combinations  similar  to 
those  of  phosphorus  and  arsenic. 

In  alloys  with  metals  it  has  the  general  feature  of 
making  them  brittle  and  hard,  but  it  has  the  added 
peculiarity  of  expanding,  like  water,  as  it  passes  from 
a  molten  to  a  solid  state.  In  castings,  therefore,  a 
very  sharp  impression  is  produced,  and  its  value  in 
type-metal  can  be  readily  understood.  Type-metal 
is  composed  (subject  to  a  considerable  number  of 
variations)  of  about  50  per  cent,  lead,  25  per  cent, 
antimony,  and  25  per  cent.  tin.  Babbitt  metal  for 
bearings  is,  according  to  one  recipe : 

7.4  per  cent,  antimony;  88.9  per  cent,  tin;  3.7  per  cent,  copper. 

Britannia  metal  is  90  per  cent,  tin  and  10  per  cent, 
antimony. 


EVERYMAN'S   CHEMISTRY 

With  copper  a  brittle  metal  is  produced  by  alloys 
of  increasing  proportions  of  antimony,  ranging  in 
color  from  copper  red  to  rose  red  and  from  crimson 
over  to  violet.  The  violet  metal  is  an  alloy  of  half 
copper  and  half  antimony. 

In  medicine  we  find  antimony  used  in  tartar  emetic. 
This  is  a  double  salt  with  potash  and  a  radical  of 
antimony  and  oxygen  as  the  two  bases  in  combina- 
tion with  tartaric  acid.  The  chemical  name  for  tartar 
emetic  is  potassium  antimonyl  tartrate,  and  the 
formula  is  K 

(SbO)C4H406. 

There  are  five  elements  in  the  nitrogen  group,  and 
bismuth  is  the  last  of  them. 


Atomic  weight  
Specific  gravity  
(Water  =  i) 
Melting-point.. 

Nitro- 
gen 

14 
0.88 

Phos- 
phorus 
31 

1.  8-2.  1 

44° 

Ar- 
senic 
175 
4-7-57 

500° 

Anti- 
mony 
1  20 
6.7 

430° 

Bis- 
muth 
208 
9.8 

208° 

By  the  time  we  reach  bismuth  we  have  a  real  metal. 
Its  combinations  with  oxygen  are  bases,  not  acids, 
and  it  is  found  chiefly  in  a  native  state.  It  looks  very 
like  antimony,  but  it  does  not  appear  to  be  poisonous. 
We  might  say  that  bismuth  is  the  old  man  of  the  fam- 
ily, and  that  he  had  outgrown  the  poisonous  quality 
that  begins  with  phosphorus,  is  at  its  peak  in  arsenic, 
and  decreases  in  antimony.  It  is  used  chiefly  in  mak- 
ing alloys,  and  in  the  form  known  as  bismuth  sub- 
nitrate  it  is  used  in  medicine  as  an  astringent  and  anti- 
septic dusting-powder. 


XI 

THE  ALKALI   METALS 

Sodium  and  Soda  —  What  It  Is  Not  —  Frequency  —  The  Chemical 
Old  Mare  —  Its  Thirst  —  Salts  and  Their  Uses  —  Manufacture  — 
Le  Blanc  —  Solvay,  Who  Rescued  Brussels  —  The  Electrolytic 
Process  —  Potassium  and  Potash  —  Plenty  of  It  —  Prospects  of 
Catching  It  —  How  Trees  and  Plants  Refuse  to  be  Deceived  — 
The  Legend  of  the  Tree  Brought  up  on  a  Bottle  which  could  not 
be  Weaned  —  Compounds  —  Lithium  —  The  Rest  of  the  Family 


most  frequent  sign  of  soda  that  meets  the 
A  American  eye  —  being  the  inviting  legend  dis- 
played by  apothecaries  and  confectioners  —  does  not 
indicate  soda  at  all.  ''Ice-cold  soda-water"  is  water 
charged  with  carbon  dioxide,  CO2.  It  obtained  its 
name  by  the  old  method  of  dissolving  sodium  bicar- 
bonate in  water  and  then  liberating  the  gas  by  a 
mild  acid  such  as  cream  of  tartar.  Such  a  preparation 
is  now  known  as  "Seidlitz  powders,"  whereas  the  old 
name  holds  to  the  water  which  has  the  bubbles  but 
not  the  soda. 

About  2^  per  cent,  of  the  crust  of  the  earth  is 
sodium,  which  makes  it  rank  seventh  in  point  of 
quantity  among  the  elements.  It  has  one  hook,  and 
is  found  chiefly  as  the  chloride,  which  we  have  already 
considered  under  salt  in  connection  with  chlorine. 
It  is  also  found  as  the  nitrate  NaNO3  in  Chile  saltpeter, 
as  the  sulphate  NaSO4  in  Glauber's  salt,  and  as 

117 


EVERYMAN'S    CHEMISTRY 

the  carbonate  in  the  alkali  deserts.  In  cryolite,  or  the 
ice  stone  of  Greenland,  it  is  found  as  a  sodium  alumin- 
ium fluoride.  It  is  found  in  countless  silicates,  and, 
as  a  result  of  rock  decay,  it  gets  into  the  soil  and  so 
into  animal  organisms.  Its  end  product  in  natural 
processes  is  salt,  and  its  habitat  the  sea. 

Sodium  is  not  found  in  a  free  state  in  nature,  be- 
cause the  pure  element,  which  is  a  light,  silvery, 
white-colored,  waxy  metal,  combines  immediately  with 
water  to  produce  sodium  hydrate  or  caustic  soda: 

Na2     +     2H2O     =     2NaOH     +     H2 
sodium         water  caustic          hydro- 

soda  gen 

To  prepare  metallic  sodium  this  process  is  reversed, 
practically,  with  the  aid  of  the  electric  current.  We 
say: 

2NaOH  =  2Na  +  H2O  +  O 

In  practice  it  isn't  so  easy.  Caustic  soda  is  heated 
in  a  tank  through  which  an  electric  current  passes. 
The  metallic  Na  formed  at  the  cathode  is  kept  away 
from  the  anode  by  an  iron  net.  At  the  anode,  OH 
groups  are  liberated  which  yield  water  and  oxygen, 
or  2OH=H2O  +  O.  The  oxygen  escapes,  but  the 
water  goes  back  to  the  other  pole,  meets  the  metallic 
sodium,  and  produces  caustic  soda  again: 

2Na  +  2H2O  =  2NaOH  +  H2 

As  a  result,  the  maximum  yield  for  a  given  quantity 
of  electricity  is  only  50  per  cent. 

This  lust  of  sodium  for  water  may  be  easily  shown 
by  cutting  with  a  knife  a  little  piece  of  metallic  sodium 
from  a  bar  and  throwing  it  into  a  pail  of  water.  It 

118 


THE   ALKALI   METALS 

will  swim  around  on  the  surface,  generating  hydrogen, 
which  escapes,  and  producing  a  solution  of  caustic 
soda  in  the  water.  It  is  well  not  to  stand  too  near, 
because  it  sputters,  and  nobody  cares  to  have  a  piece 
of  sodium  busy  with  water  or  moisture,  or  even  a 
solution  of  caustic  soda,  in  his  eye  or  on  his  counte- 
nance. 

Metallic  sodium  is  used  in  metallurgy,  and  is  kept 
under  kerosene  or  in  some  liquid  which  contains  no 
oxygen.  It  is  in  the  form  of  the  carbonate  as  soda  or 
soda  ash,  as  it  is  called,  Na2CO3,  and  as  the  bicarbonate 
NaHCOs,  and  as  lye  or  caustic  soda  or  sodium  hydrox- 
ide, NaOH,  that  it  finds  its  great  use.  Note,  please, 
that  sodium  bicarbonate  is  really  a  kind  of  half- 
carbonate,  in  that  to  one  radical  of  the  carbonic  acid 
we  have  one  sodium  and  one  hydrogen  atom,  whereas 
in  the  carbonate  or  monocarbonate  there  are  two  Na 
atoms.  We  said,  in  considering  sulphuric  acid,  that 
if  it  were  called  the  old  horse  of  chemistry,  we  should 
have  to  regard  soda  as  the  old  mare.  It  is  the  grand 
universal  alkali,  and  it  is  used  everywhere,  constantly. 
A  few  of  its  uses  are  given  in  Chemistry  of  Common 
Things,  by  Sadtler,  elsewhere  referred  to,  from  which 
we  shall  copy: 


Salt  NaCl 

Sodium  hydroxide          NaOH 

(Caustic  soda,  lye) 
Sodium  carbonate          Na2COa 

(Soda  ash,  sal  soda, 

soda  crystal) 
Sodium  bicarbonate       NaHCOa 

(Cooking  soda) 
Sodium  sulphate  Na2SO4 

(Glauber's  salt) 

Sodium  phosphate          Na2HPO4 
Sodium  monophosphate  NaH2PC>4 
Sodium  triphosphate      Na3P04 
9  119 


Used:  Condiment.     Chemicals. 
Soap.     Chemicals. 

Cleaning.    Soap  powders. 
Chemicals.     Scouring. 

Baking  powders.  Chemicals. 

Medicine. 
Glass-making.     Wood  pulp. 

Medicine. 
Medicine. 

Baking  powder  (Ryzon). 
Softening  water. 


EVERYMAN'S   CHEMISTRY 


Sodium  thiosulphate 
(Sodium  hyposul- 
phite) 

Sodium  nitrate 

Sodium  borate 
(Borax) 

Sodium  silicate 
(Water  glass) 

Sodium  chlorate 

Sodium  peroxide 
Sodium  dichromate 


NaHO3 
Na2B4O7 

Na2SiO3 


NaClOs 

Na2O2 
Na2Cr2O7 


Used:  Tanning  and  photography. 


Agriculture.     Chemicals. 
Cleaning.     Mild  alkali. 

Soap-filling.         Silk-dyeing. 

Bandages.          Preserving 

eggs. 
Pyrotechnics.       Explosives. 

Textile  work. 
Bleaching. 
Tanning. 


And  this  is  only  a  hint  of  its  many  uses.  Making 
soda  is  one  of  the  leading  chemical  industries  and  the 
process  always  starts  with  salt.  The  old  standard 
method  of  producing  it  was  that  of  Nicholas  le  Blanc, 
the  domestic  physician  to  the  Duke  of  Orleans,  who 
in  turn  provided  capital  for  the  start  of  the  industry. 
The  French  Revolution  came  along  and  left  poor  old 
Doctor  le  Blanc  stranded,  while  the  industry,  as  in- 
dustries have  a  way  of  doing,  quietly  moved  over  to 
England. 

This  is  a  great  trick  of  industries  which  are  not 
interested  in  political  economy  or  human  welfare  ex- 
cept as  it  may  affect  production.  At  the  time  of  this 
writing  there  is  a  movement  of  electrochemical  in- 
dustries from  Niagara  Falls,  where  they  started,  to 
Norway,  where  there  is  cheaper  power  and  more  of  it. 
Whether  we  shall  continue  to  waste  our  precious 
power  by  permitting  the  continued  waste  of  the  wicked 
beehive  coke-ovens,  which  burn  up  everything  except 
the  coke  produced  and  do  not  even  conserve  the 
power  that  goes  to  waste;  whether  Niagara  Falls  will 
be  turned  over  entirely  to  industry  or  not;  whether 
our  conservation  laws  in  the  United  States  will  be 
modified  so  as  to  permit  the  profitable  industrial  use 


120 


THE   ALKALI   METALS 

of  available  water-power  sites — are  all  questions  that 
are  in  the  air,  and,  while  they  are  in  process  of  settle- 
ment, the  electrochemical  industry  will  probably  set- 
tle down  somewhere  and  take  a  lead  for  £ fty  or  a 
hundred  years. 

The  Le  Blanc  process  consisted  in  treating  salt  with 
sulphuric  acid,  thus  producing  sulphate  of  sodium, 
Na2SO4,  or  salt  cake,  as  it  is  called.  This  was  heated 
with  coal  and  limestone  (calcium  carbonate)  until  the 
mass  had  fluxed,  when  the  reaction  took  place.  This 
brought  the  carbonic-acid  radical  over  to  the  soda, 
and  the  sulphuric  acid  produced  sulphate  of  lime  or 
gypsum.  The  alkalies  changed  acids  in  the  process. 
That  is  the  reason  why  the  soda,  being  obtained  from 
the  flux,  obtained  its  name  of  soda  ash.  In  the  first 
process  of  making  salt  cake,  chlorine  was  liberated, 
which  was  conserved  as  hydrochloric  (or  muriatic) 
acid,  HC1,  and  it  was  also  used  to  make  bleaching- 
powder,  which  is  obtained  by  passing  chlorine  through 
a  series  of  chambers  containing  slacked  lime.  The 
Le  Blanc  process  is  now  nearly  obsolete. 

In  1 86 1  Ernest  Solvay,  of  Brussels,  patented  the 
Ammonia  Process,  which  is  that  by  which  the  major 
portion  of  the  soda  used  to-day  is  made,  although  we 
shall  soon  note  another  process,  one  that  is  crowding 
it  whenever  there  is  sufficient  power  available  for 
electricity. 

In  the  Solvay  process,  common  salt,  NaCl,  is  treated 
with  ammonium  bicarbonate,  or  successively  with 
ammonia  and  with  carbonic-acid  gas,  at  a  low  tem- 
perature. Sodium  bicarbonate  and  ammonium  chlo- 
ride are  formed,  and  the  sodium  bicarbonate,  being 
nearly  insoluble  in  a  solution  of  ammonium  chloride, 
NH4C1,  it  precipitates  out.  The  mother  liquor  is 
drawn  off,  treated  with  caustic  lime,  which  frees  the 

121 


EVERYMAN'S    CHEMISTRY 

ammonia,  NH3,  and  produces  calcium  chloride.  The 
NH3  is  saved,  and  the  calcium  chloride  is  waste,  or 
nearly  so.  It  is  used  to  keep  dusty  roads  moistened, 
because  it  draws  water  from  the  air.  It  is  also  used 
to  make  anti-freezing  mixtures,  but  if  any  one  will 
discover  a  steady  use  for  large  quantities  of  it  he  will 
have  no  trouble  in  getting  invitations  to  dinner. 
Instead  of  using  lime,  it  is  possible  to  employ  mag- 
nesia. From  the  magnesium  chloride  the  chlorine 
may  be  regained  by  heating,  and  the  magnesium  oxide 
or  magnesia,  which  is  formed  as  soon  as  the  chlorine 
leaves  it,  may  be  used  over  and  over  again. 

The  bicarbonate  of  soda  is  changed  to  the  carbonate 
by  heating,  and  caustic  soda,  NaOH,  is  made  by  treat- 
ing the  carbonate  with  quicklime.  It  was  Ernest 
Solvay,  who  had  amassed  great  wealth  from  the  soda 
industry  in  Europe  and  America,  who  paid  the  vast 
indemnity  demanded  by  the  German  invaders  as  their 
price  for  not  destroying  the  city  of  Brussels. 

A  still  newer  method,  originating  in  America  and 
developed  by  various  American  chemists,  is  the  elec- 
trolytic process.  It  is  not  so  simple  as  it  looks,  but 
in  effect  the  salt  brine  is  led  into  an  electrolytic  cell. 
A  current  of  electricity  is  passed  through  which  splits 
the  Na  from  the  Cl,  each  element  going  to  its  respec- 
tive pole.  The  sodium  combines  with  the  water  to 
produce  caustic  soda,  as  described  in  the  beginning 
of  this  chapter,  and  the  chlorine  is  saved,  compressed, 
and  cooled  until  a  liquid  condition  is  reached,  and  is 
then  sold  to  bleacheries  and  to  chemical  works  for 
chlorination  processes  and  for  the  destruction  of  bacilli 
in  city  water. 

Potassium  (K,  for  the  Latin  word  kalium)  is  the 
elemental  or  metallic  potassium,  while  potash  is  the 

122 


THE   ALKALI    METALS 

common  term  for  the  carbonate.  The  nomenclature, 
however,  is  a  little  loose,  and  "potash  salts"  is  used 
to  indicate  salts  of  potassium,  but  chiefly  the  chloride. 
It  is  a  very  close  cousin  to  sodium.  It  has  also  only 
one  bond,  and  in  a  metallic  state  it  is  soft,  waxy,  of  a 
silvery- white  color,  and  changes  over  to  the  hydroxide 
or  caustic  potash,  KOH,  on  being  brought  into  contact 
with  water.  Indeed,  a  piece  thrown  into  water  will 
dance  about,  liberating  hydrogen  and  casting  caustic 
potash  into  solution  at  such  a  lively  rate  that  enough 
heat  is  generated  to  set  the  hydrogen  afire. 

Potassium  is  not  found  in  a  free  state  in  nature,  for 
the  obvious  reason  that  it  will  not  remain  free,  but 
it  is  very  wide-spread.  In  the  form  of  nitrate,  KNOa, or 
saltpeter,  it  was  formerly  found  in  deposits  in  India, 
but  these  have  long  been  exhausted.  They  were  by 
no  means  so  extensive  as  the  Chilean  beds  of  nitrate 
of  sodium.  The  great  source  of  supply  has  been  in 
the  deposits  of  Germany,  in  Hanover,  Westphalia, 
and  in  Alsace,  and  at  the  time  of  the  present  writ- 
ing there  is  a  serious  potash  famine  in  the  United 
States. 

The  situation  reminds  one  of  the  old  line  about 
"  Water,  water  everywhere,  and  not  a  drop  to  drink," 
because  there  is  any  amount  of  potassium  to  be  found 
in  this  country.  The  greatest  supply  is  in  the  wide- 
spread mineral  called  feldspar,  which  contains  up 
to  17  per  cent.  K,  but,  alas!  it  is  bound  up  with 
aluminium  as  a  double  silicate,  and  it  is  insoluble. 
That  is  to  say,  the  potash  is  there  in  the  feldspar,  but 
it  is  in  the  form  of  glass  and  pottery.  So  far,  the  only 
way  to  get  it  out  is  by  the  heat  of  the  electric  arc, 
and  that  takes  great  quantities  of  cheap  power.  This 
problem  is  sure  to  be  solved  some  day;  there  are 
patents  by  the  hundred  on  various  processes  to  do  it. 

123 


EVERYMAN'S    CHEMISTRY 

But  no  large  plant  of  importance  is  in  operation  yet, 
nor  is  there,  so  far  as  we  know,  any  in  process  of  con- 
struction at  this  time.  As  we  have  said  before,  the 
American  business  man  does  not  like  to  spend  money 
on  experiments,  and  every  one  of  these  processes  re- 
quires factory  demonstration  to  prove  itself.  And 
yet,  so  hopeful  are  men  of  the  solution  of  this  riddle 
that  a  syndicate  of  miners  in  Colorado  are,  at  the 
time  of  this  writing,  setting  aside  daily  two  thousand 
tons  of  finely  ground  and  washed  feldspar  against  the 
time  when  somebody  wjll  appear  with  a  successful 
process.  There  is  some  potash  in  sea- water,  and  the 
giant  kelp  of  the  Pacific  coast  absorbs  it,  so  that  it 
contains  from  10  to  40  per  cent,  of  KC1.  Several 
large  works  are  in  process  of  construction  in  California 
to  secure  the  needed  potash  from  this  giant  seaweed, 
but  these  will  produce  only  a  very  small  fraction  of  the 
potash  needed.  A  very  interesting  suggestion  was 
lately  made  by  a  well-known  chemical  writer.  He  was 
visiting  California,  and  observed  the  great  activity 
in  building  plants  for  the  commercial  recovery  of 
potash.  Here  are  these  big  seaweeds,  thought  he, 
which  take  up  a  great  deal  of  potash  from  the  very 
small  amount  held  in  solution  in  the  ocean.  The 
plants  do  not  take  in  sodium  salt,  of  which  there  is 
a  much  greater  amount  in  the  sea.  The  separation  is 
accomplished  by  some  kind  of  semi-permeable  mem- 
brane which  lets  through  potash  salts  and  iodine,  but 
keeps  the  soda  salts  out.  "What  kind  of  a  membrane 
is  it?"  he  asked.  "What  is  the  character  of  the  semi- 
permeable  diaphragm,  or,  generally,  what  is  the 
mechanism  of  the  concentration  process?"  Here  is 
another  nut  to  crack  in  physical  chemistry.  If  the 
nature  of  the  process  by  which  the  giant  kelps  take  up 
the  potash  salts  and  leave  the  compounds  of  sodium 

124 


THE   ALKALI    METALS 

behind  were  known,  we  could  put  tanks  with  walls 
of  such  a  nature  into  the  sea  and  enjoy  watching  them 
fill  themselves  with  pure  solutions  of  potash.  Then 
we  might  concentrate  the  liquor,  crystallize  out  the 
potassium  salt,  dry  it,  sell  it,  and  send  for  another 
box  of  those  fifty-cent  cigars.  It  seems  likely,  though, 
that  even  if  we  knew  how  to  turn  the  trick,  it  would 
only  work  with  dilute  solutions.  Then  the  cost  of 
concentration  might  be  too  great  for  us  to  buy  the 
cigars,  after  all. 

Another  source  of  supply  is  in  the  saline  deposits 
of  dry  lakes  in  southern  Utah  and  California.  These 
are  being  operated  in  a  small  way,  but  not  nearly 
enough  for  our  needs.  It  is  said  to  cost  the  German 
syndicate  about  $20  a  ton  to  mine  and  prepare  the 
muriate  of  potash  for  market,  and  they  get  about 
$40  a  ton  for  it.  Or,  rather,  that  was  the  case  before 
August  i,  1914.  Since  then  as  high  as  $450  a  ton  has 
been  paid  for  it. 

Trees  and  plants  must  have  potash.  The  clearest 
evidence  that  trees  need  it  is  the  amount  of  it  we 
find  in  wood  ashes,  in  which  it  runs  as  high  as  5  or 
6  per  cent.,  despite  the  fact  that  some  of  it  goes  up  in 
smoke.  Indeed,  that  is  where  it  got  its  English  name — 
the  ash  from  under  the  pot.  Then,  to  be  'scruciating 
elegant,  we  have  Latinized  the  word  to  potassium. 
The  Germans  stick  to  the  word  that  came  from  the 
Arabic  alchemists,  and  call  it  kalium,  which  is  related 
to  the  word  alkali. 

Just  what  role  potash  plays  in  the  nutrition  of 
plants  it  is  hard  to  tell.  It  used  to  be  so  simp  e  to 
think  of  soil  as  consisting  of  so  much  clay  (silicate  of 
aluminium),  so  much  sand  (silica),  with  so  much 
fixed  nitrogen,  potash,  and  phosphates,  and  nothing 
else.  The  idea  was  that  after  the  chemist  had  done  a 

125 


EVERYMAN'S    CHEMISTRY 

little  fuddling  with  it  and  made  his  analysis,  the 
enlightened  farmer  would  know  exactly  what  to  do. 
Things  are  so  easy  when  we  know  only  a  little!  Now 
the  chemist  does  rightly  and  properly  analyze  soils, 
and  the  enlightened  farmer  is  greatly  helped  by  his 
results,  but  remember,  please,  that  agriculture  comes 
more  properly  under  the  head  of  plant  physiology  than 
under  chemistry.  The  soil  teems  with  life.  In  sum- 
mer from  half  a  million  to  a  million  bacteria  are  found 
in  a  single  grain  weight  of  soil.  Besides  bacteria,  it 
has  yeasts,  molds,  fungi,  protozoa,  amoebae,  nema- 
todes,  and  worms.  Then  there  is  humus,  which  is 
fermenting  organic  matter.  The  nature  of  soils  is 
one  of  the  most  complex  of  studies.  There  is,  however, 
a  gross  chemical  aspect  of  soils  which  is  the  basis  of 
the  fertilizer  business,  if  not  of  the  use  of  fertilizers, 
and  this  we  shall  consider.  We  have  discussed  the 
need  of  fixed  nitrogen,  and  we  know  the  need  of  phos- 
phoric-acid salts.  What  potash  seems  to  do  in  the 
economy  of  plant  life  is  to  act  as  a  catalyst  in  that 
marvelous  synthetic  laboratory  in  the  plants  which 
mates  up  carbon  dioxide  and  water  to  sugar  and  starch 
and  then  to  cellulose.  The  richer  plants  are  in  carbo- 
hydrates (sugars,  starch,  etc.)  the  more  potash  they 
seem  to  contain.  It  seems  to  aid  in  the  growth  of 
strong,  vigorous  roots  and  stems,  and  in  neutralizing 
plant  acids  it  appears  to  affect  favorably  the  flavor  of 
fruits.  It  is  claimed  also  that  plants  become  more 
resistant  to  disease  if  adequate  potash  is  supplied. 
The  reason  why  sodium  may  not  be  substituted  for 
potassium  in  plant  economy  is  possibly  because  the 
potash  salts  diffuse  more  readily  through  the  cells 
than  those  of  soda,  or  because  of  the  greater  liking 
that  potash  salts  have  for  water  than  soda  salts.  The 
fact  is,  however,  you  cannot  substitute  soda  for  potash 

126 


THE   ALKALI    METALS 

in  agriculture  with  success — so  far.  The  plants  will 
discriminate. 

The  natural  history  of  potash  is  like  that  of  sodium. 
It  exists  principally  in  the  silicates,  in  feldspar  and 
mica  especially,  and  upon  the  decay  of  these  minerals 
some  of  it  is  carried  into  the  soil  and  thence  to  plants. 
They  must  have  considerable  of  it  for  lusty  growth, 
and,  as  we  have  intimated,  many  kinds  of  vegetation 
seem  to  need  it  for  flavor.  The  legend  is  told  by  a 
gentleman  with  a  lively  imagination  of  a  farmer  who 
had  a  wonderful  apple-orchard  in  which  everything 
was  done  which  science  could  provide  for  his  trees. 
Finally,  on  the  ground  that  a  tree  is,  after  all,  only  an 
osmotic  engine,  the  lord  of  the  orchard  bethought 
himself  that  he  could  give  the  needed  fertilizer  to  one 
of  his  trees  by  bringing  the  constituent  parts  of  the 
needed  manure  or  "tree  food "  into  its  circulation  from 
a  solution  contained  in  a  bottle  and  fed  by  gravity 
through  a  gimlet-hole.  The  tree  took  by  gravity 
through  the  gimlet-hole  far  more  than  its  sluggish 
roots  would  absorb,  and  its  carefully  balanced  rations 
of  salts  in  solution  soon  began  to  show  results.  In 
size,  taste,  and  quality  they  outshone  any  apples  ever 
grown,  but,  alas!  when  cold  weather  came  the  tree 
had  grown  so  accustomed  to  being  fed  by  the  bottle 
that  its  roots  had  atrophied,  and  the  farmer  was 
unable  to  wean  it.  We  do  not  know  the  fate  of  that 
tree — whether  it  turned  out  well  or  badly,  and  we 
never  have  brought  ourselves  to  believe  in  it  thor- 
oughly. We  fear  it  was  cut  off  in  the  blossom  of  its 
youth. 

The  compounds  of  potassium  are  so  analogous  to 
those  of  sodium  that  we  shall  not  mention  them  in 
great  detail.  The  chloride  and  sulphate  are  used  for 
fertilizer  materials,  the  bromide  is  used  as  a  medi- 

127 


EVERYMAN'S   CHEMISTRY 

cine,  largely  for  its  sedative  effect,  and  the  iodide, 
like  sodium  iodide,  is  used  also  in  medicine.  The 
fluoride  has  the  peculiar  quality  of  forming  the  double 
halide  FK,  FH;  and  the  cyanide,  like  the  cyanide  of 
sodium,  is  used  to  extract  gold  from  its  ores.  The 
nitrate,  KNO3,  is  one  of  the  constituents  of  gunpowder 
in  the  proportion  75  saltpeter  or  KNO3,  10  carbon 
(charcoal),  and  15  sulphur.  When  it  explodes  this 
is  about  what  happens: 

2KN08     +    S    +    3C     -     K2S    +    N«     +  3C02 

potassium        sul-         car-         potas-       nitro-  carbon 

nitrate         phur        bon          sium          gen  dioxide 

sulphide 

This  is  not  entirely  correct,  because  the  remaining 
potash  is  not  all  in  the  form  of  K2S.  But  the  gases 
are  chiefly  CO2  and  some  CO.  The  tension  of  the 
gaseous  products  is  about  6,500  atmospheres  (96,000 
pounds  to  the  square  inch)  and  the  temperature 
about  2,200°  centigrade. 

The  silicate  of  K  is  very  like  Na  silicate.  The 
sulphides  are  not  very  stable  and  oxidize  easily. 

Lithium,  sodium,  and  potassium  constitute  the  prin- 
cipal members  of  the  group  known  as  the  alkali 
metals,  and  lithium  is  the  first  of  the  series.  None  is 
found  free  in  nature,  all  are  widely  distributed,  but 
lithium  is  found  only  in  small  quantities.  It  occurs 
chiefly  as  the  silicate  in  lepidolite  or  lithia  mica,  as  the 
phosphate  in  triphylite,  and  in  company  with  Al,  Na, 
and  Fl  in  amblygonite.  Finally  it  is  met  with  in  the 
ashes  of  certain  plants,  such  as  tobacco,  showing  that 
it  is  contained  in  the  soil.  Minute  traces  of  it  are  found 
in  many  minerals. 

Metallic  lithium,  prepared  by  electrolysis  of  the 

128 


THE   ALKALI   METALS 

fused  chloride,  is  the  lightest  of  all  solid  substances 
except  frozen  hydrogen.  It  is  but  little  over  half  the 
weight  (less  than  six-tenths)  of  water,  and  it  floats  on 
kerosene.  It  is  silvery  white,  but  tarnishes  rapidly 
on  exposure  to  moist  air.  With  oxygen  it  produces 
lithium  oxide,  Li2O,  and  this  goes  over  into  the  hy- 
droxide, LiOH,  which  dissolves  in  water,  producing  a 
strongly  alkaline  solution,  like  caustic  soda,  NaOH, 
or  caustic  potash,  KOH. 

The  chloride,  LiCl,  is  very  soluble  and  takes  on 
water  from  the  air. 

The  carbonate,  Li2C03,  is  not  very  soluble  in  water, 
in  which  it  differs  from  the  Na  and  K  carbonates. 

The  phosphate,  Li3PO4,  shows  the  same  peculiarity. 

Lithium  salts  are  used  in  medicine.  There  is  but 
little  if  any  technical  use  for  the  metal  or  its  com- 
pounds at  present. 

The  other  two  members  of  the  family  are  rubidium 
and  caesium,  which  we  shall  not  consider  further  than 
to  note  that  they  are  also  soft,  silvery- white  metals, 
and  we  mention  them  only  to  show  the  family  rela- 
tion, how  they  progress  up  in  one  respect  and  down 
in  another,  just  like  some  other  families  of  elements: 

Potas-  Ru-  Caesi- 

Lithium  Sodium  slum  bidium  um 

Atomic  weight 6.94  23.0  39 .10  85.45  132.81 

Specific  gravity 0.534  0.971  0.862  1.532  1.87 

(Water  =  i) 

Melting-point 186°  97°  62°  62°  26° 

Boiling-point 1400®  877°  700°  696°  670° 


XII 

SAND   AND   CLAY 

The  Enormous  Supply  of  Silicon — Its  Inert  Ways — The  Silicon  Man — 
Glass  History — The  Cautious  Venetians  and  the  Glass-makers 
Who  Stepped  Heavenward — Kinds  of  Glass — Coloring — Boston's 
Purple  Windows — Glass-making  in  the  United  States — The  Art 
of  It — Aluminium — The  Young  Fellow  of  Twenty- two  Who 
Made  It — The  Frenchman  Who  Did  the  Same  Thing — Value  of 
Backing  by  Pittsburgh  Millionaires — Clay — Brick — Pottery — 
Glaze — Different  Kinds  of  Clay — Feldspar — Fuller's  Earth — 
Mica — Note  on  Boron  and  Borax 

ABOUT  50  per  cent,  of  the  solid  crust  of  the 
/x  globe  is  oxygen,  and  about  25  per  cent,  of  it 
is  silicon.  But  silicon  is  not  found  in  a  free  state  in 
nature;  it  is  too  fond  of  oxygen.  It  belongs  to  the 
same  group  as  carbon,  and  has,  consequently,  four 
hooks  to  the  atom.  It  can  be  driven  from  its  combi- 
nations in  the  laboratory  without  great  difficulty,  but 
it  burns  back  to  silicon  dioxide,  or  silica,  SO2,  at  a 
comparatively  low  temperature. 

In  a  pure  state  it  is  known  in  three  forms:  as  a 
brown  amorphous  powder,  as  graphitoidal  silicon  (in 
black  flakes),  and  as  crystalline  (in  dark,  iron-gray 
crystals). 

As  silica,  SiO2,  it  is  sand,  and  it  constitutes  from 
20  to  35  per  cent,  of  granite  and  primitive  rock,  and 
along  with  compounds  of  aluminium,  which  consti- 
tute clay,  it  is  the  earth. 

It  behaves  like  carbon  in  its  combinations,  except 

130 


SAND   AND   CLAY 

that  it  may  be  said  to  regard  this  world  as  a  cold, 
bleak  place,  and  it  does  not  care  for  combining  much 
except  with  oxygen.  It  can  hook  up  its  atoms  together 
in  chains,  as  carbon  does,  and  the  number  of  imagin- 
able silicon  compounds  is  beyond  compute;  but  when 
the  chemist  with  infinite  pains  has  negotiated  a  num- 
ber of  silicon  compounds  that  correspond  to  those 
of  carbon,  such  as,  for  instance,  silicon  chloroform, 
SiHCl3  (chloroform  being  CHC13)  ?  and  similar  bodies, 
they  disintegrate  on  contact  with  water  or  in  the  air 
and  the  silicon  atom  will  yoke  itself  up  with  oxygen 
again  to  SiO2.  It  may  be  livelier  at  high  temperatures, 
but  that  is  just  where  we  cannot  follow  it.  Perhaps 
we  can  get  a  better  idea  of  this  feature  of  the  nature  of 
silicon  by  quoting  some  verses  called  "The  Silicon 
Man,*'  which  appeared  several  years  ago  in  The  Per- 
colator, issued  by  the  Chemists'  Club  of  New  York. 
The  verses  will  hardly  stand  alongside  of  the  rhapso- 
dies of  Milt  on,  which  are  occasionally  quoted  in  popular 
treatises  on  chemistry;  indeed,  their  feet  are  so  shaky 
that  they  can  hardly  stand  at  all ;  but  they  may  throw 
a  little  light  to  the  chemical  imagination  as  to  what 
silicon  would  do  if  it  only  had  the  temperature — and 
the  audience. 

THE  SILICON  MAN 

I  saw  a  glowing  Silicon  Man 

Within  my  chamber  fire, 
And  heard  him  cry  in  agony, 

"More  fuel,  or  I  expire!" 

So  from  the  wood-pile  I  brought  in 

Some  pine  and  hickory, 
And  as  I  fed  it  to  the  flames 

He  straightway  piped  his  eye. 
131 


EVERYMAN'S   CHEMISTRY 

"I  am,"  said  he,  "John  Silicon, 

And  I  am  so  constructed 
That  Silicon's  my  substitute; 

My  carbon's  all  deducted. 

"My  tissues,  nerves,  and  viscera 

Show  this  phenomenon: 
That  just  as  you  of  carbon  are, 
I  am  of  silicon. 

"In  other  features  we're  the  same 
(More  fuel!  The  coal  flame  twinges!) 

The  point  is  that  our  molecules 
Are   different  in  their  hinges. 

"You  call  those  things  organic  which 

By  nature  are  based  on 
Some  carbon  atoms — more  or  less — 

We  hold  to  silicon. 

"At  temperatures  such  as  you  know," 
Said  he,  "we  freeze.     We  turn 

To  consciousness  again  when  you 
Would  sizzle  up  and  burn." 

Now  this  peculiar  Silicon  Man 
(The  fire  was  bright  as  gold) 

Seemed  suffering,  and  so  I  gave 
Him  whisky  for  his  cold. 

He  liked  it;   said  he  never  felt 

So  well  as  when  he  had 
A  taste  of  liquor  on  his  tongue; 

It  was  his  little  fad 

To  make  an  ethyl  silicohol 

By  substituting  Si 
For  carbon  in  the  alcohol; 

He  called  it  Hades  Rye. 
132 


SAND    AND   CLAY 

The  Silicon  Man  drank  more  and  more, 

He  grew  full  talkative, 
And  drank  the  substituted  dram 

As  though  he  were  a  sieve. 

He  said  he'd  lived,  lo,  many  a  year — 

An  old,  old  man  was  he — 
And  yet  he  had  not  lived  so  much, 

Because,  as  you  can  see, 

At  ordinary  temp'rature 

His  soul  was  frozen  dead, 
And  only  resurrected  when 

The  flames  were  blazing  red. 

"This  life,"  said  he,  "is  not  so  bad 

When  once  you're  used  to  it: 
To  freeze  whene'er  the  fire  goes  out 
And  waken  when  it's  lit. 

"The  orthodox  concept  of  hell 

Is  partly  right,"  said  he, 
"The  heresy  lies  in  the  claim 

That  heat  is  misery. 

"My  needs,"  said  he,  "are  very  few; 

I  want  no  meat  nor  bread, 
And  if  you  feed  the  fire  well 

You'll  never  find  me  dead." 

But  when  at  last  my  bedtime  came 

I  heard  a  painful  shout; 
It  was  a  cry  for  silicohol 

Just  as  the  fire  went  out. 

We  need  not  worry  much  about  the  organic  silicon 
compounds.  There  are  a  number  of  stable  ones  found 
in  nature — grains  need  it  in  their  stalks,  and  the 


EVERYMAN'S    CHEMISTRY 

feathers  of  birds  and  the  scales  of  fish  carry  them. 
But  the  great  mass  of  it  is  in  the  form  of  silica,  SiO2, 
and  as  such  it  is  found  in  various  forms.  It  is  found 
in  a  fine  state  of  division  consisting  of  the  scales  of 
extinct  diatoms,  and  known  as  kieselguhr,  or  diatoma- 
ceous  earth.  This  is  used  for  filtering,  in  the  prepara- 
tion of  dynamite,  and  other  purposes.  Then  we  find 
it  as  quartz  in  crystals,  and  in  another  crystalline 
form  as  tridymite  in  porphyry  and  other  rocks,  and  in 
a  quasi-amorphous  state  with  water  locked  in  as  in 
opals.  It  melts  to  a  colorless  glass,  is  insoluble  in 
water,  and  is  not  attacked  by  acids  except  hydro- 
fluoric. The  amorphous  silica  is  soluble  in  alkali  if 
in  a  finely  divided  state,  but,  when  fused,  alkali  only 
attacks  it  slightly.  Silica  is  the  anhydrid  of  .an  acid 
which  would  naturally  be  obtained  by  adding  water, 
except  that  pure  silicic  acid  as  such  is  not  known  in  a 
free  state.  But  its  salts  are  known.  Many  silicates 
are  prepared  artificially. 

Silicates  of  soda  and  of  potash  are  soluble  in  water; 
other  silicates  are  not. 

By  bringing  sand  and  salt  (NaCl)  and  coke  to- 
gether and  heating  them  in  an  electric  arc,  Acheson 
produced  a  crystalline  body  composed  substantially 
of  the  two  elements,  or  carbide  of  silicon,  CSi.  This 
is  well  known  as  carborundum,  and  is  made  at  Niagara 
Falls.  It  is  so  hard  as  to  scratch  rubies  and  is  not 
acted  upon  by  acids  at  ordinary  temperatures.  It  is 
one  of  the  hardest  abrasives,  and  has  found  wide  use 
as  a  substitute  for  emery.  There  are  silicides  of  many 
metals,  but  their  relation  to  iron  and  steel  we  shall 
discuss  when  we  come  to  the  iron  and  steel  industry. 

The  most  extended  use  of  silica,  SiO2,  in  industry  is 
in  glass  and  pottery  making. 

Glass  is  a  solid  solution  of  indefinite  composition, 


SAND   AND    CLAY 

produced  by  the  fusing  of  sand  (silica)  with  the  oxides 
of  two  or  more  metals.  It  has  no  definite  molecular 
structure  like  a  crystalline  substance;  its  component 
parts  present  the  same  indefinite  arrangement  as  is 
found  in  a  solution.  Glass  has  the  property  of  being 
transparent  and  rigid  at  ordinary  temperatures,  but 
plastic  when  heated.  Its  properties  change  according 
to  its  composition,  and,  while  we  may  say,  generally, 
that  it  is  insoluble,  this  is  only  approximately  true. 
Acids  affect  it  (always  excepting  hydrofluoric  acid) 
less  than  alkalies,  but  even  water,  especially  under 
high  pressure  and  high  temperature,  will  corrode  some 
glass. 

Glass  was  made  as  far  back  as  1400  B.C.,  and  at 
the  dawn  of  the  Christian  era  it  was  a  thriving  in- 
dustry. It  degenerated  in  medieval  days,  chiefly  be- 
cause the  natron,  or  natural  sodium  carbonate  which 
the  Romans  used,  was  no  more  availed  of,  and  impure 
wood  ashes  were  used  in  the  place  of  it.  The  Venetians 
kept  up  the  quality  of  their  product  by  using  the  ash 
of  a  sea  plant  which  they  called  kali  for  their  base. 
In  the  palmy  days  the  Venetians  would  not  let  a  man 
escape  from  the  country  if  he  knew  how  to  make 
glass.  If  he  did,  they  followed  him  up,  and  if  they 
found  him  he  was  supposed  to  have  a  harp  by  the 
time  they  finished  with  him. 

If  sand,  which  is  nearly  pure  SiO2,  could  be  melted 
with  ease,  it  would  be  ideal  glass — quartz  glass — but 
it  is  too  hard  to  fuse.  So  the  maker  adds  fluxes.  As 
soon  as  you  add  soda  to  the  sand,  down  comes  the 
melting-point  of  the  mixture,  and  soda  is  the  most 
convenient  flux.  But  when  the  glass  is  made,  the  less 
soda  you  have  in  it  the  better  the  product  is  likely  to 
be,  for  silicate  of  soda  is  very  soluble.  Then,  too,  the 
more  soda  glass  contains  the  more  will  it  expand  and 


EVERYMAN'S   CHEMISTRY 

contract  in  heat  and  cold — and  so  be  likely  to  break — 
and  the  lower  is  its  tensile  strength.  To  overcome  the 
solubility  another  base  is  added,  and  this  is  usually 
lime.  Not  always  enough  lime,  however,  because  the 
more  lime  the  glass-maker  puts  in  the  more  fuel  he 
needs  for  melting,  and  sometimes  he  is  of  an  econom- 
ical turn  of  mind.  Then,  too,  sometimes  the  buyer 
wants  his  window-glass  or  his  bottles  a  little  cheaper 
than  he  has  a  right  to  ask  for. 

If  a  more  brilliant  and  denser  glass  is  wanted,  lead 
oxide  is  added,  and  the  lead  becomes  a  silicate. 

If  potash  is  used  in  the  place  of  soda,  the  differences 
are  marked.  For  instance,  a  vessel  made  of  lime- 
soda  glass  without  enough  lime  in  it  becomes  covered 
in  time  with  a  whitish  powder  which  leaves  the  glass 
rough.  That  is,  the  soda  oozes  out  and  by  exposure 
to  the  air  becomes  carbonate  of  soda,  which  is  a  whitish 
powder.  Potash  glass  without  enough  lime  will  also 
sweat  out  potash,  but  the  carbonate  of  potash  as 
formed  draws  on  water  from  the  air  and  so  runs  off 
without  injury  to  the  surface  of  the  glass.  Potash 
glass  has  a  bell-like  ring  which  soda  glass  has  not, 
due  to  greater  elasticity,  and  this  makes  it  more  de- 
sirable for  tableware.  Generally  speaking,  potash 
glass  is  cleaner  and  brighter. 

Cut  glass  is  a  potash-lead  solution;  but  there  being 
no  potash  available  in  the  United  States  these  days, 
it  is  made  with  soda,  and  it  is  hardly  likely  to  stay 
as  bright  as  if  it  were  made  as  before.  On  the  other 
hand,  by  that  strategy  which  constitutes  research,  a 
better  electric-light  bulb  has  been  produced  with  soda 
than  was  formerly  made  with  potash. 

Laboratory  glass  is  now  made  in  the  United  States 
in  large  quantities,  and  the  problem  is  similar  to  that 
for  making  glass  kitchenware — for,  if  we  but  knew  it, 

136 


SAND   AND    CLAY 

every  kitchen  is  a  laboratory.  The  product  must 
have  a  low  coefficient  of  expansion  and  high  tensile 
strength.  That  is,  it  must  not  expand  and  contract 
too  much  with  heat  and  cold,  because  if,  say,  hot 
water  is  poured  into  a  vessel  it  will  expand  where  the 
hot  water  is,  but  not  above  it,  and  there  comes  the 
breaking  strain.  And  its  tensile  strength  should  be 
high,  so  that  if  you  drop  it  on  the  floor  it  will  hold  to- 
gether with  sufficient  tenseness  and  not  break.  The 
glass-maker  lowers  the  coefficient  of  expansion  by 
adding  boric  oxide,  and  he  adds  silica  and  aluminium 
to  increase  the  tensile  strength.  Here  are  a  number 
of  kinds  of  glass  and  their  special  uses: 

Silica,  with  soda  and  lime  or  soda-lime  glass.  Used 
for  window-glass,  chemical  glassware,  and  bottles. 

Silica,  with  soda,  lime,  and  aluminium.  Used  for 
beer,  wine,  and  spirit  bottles,  owing  to  strength  and 
insolubility. 

Silica,  with  potash  and  lime.  Bohemian  glass,  for 
tableware. 

Silica,  with  potash  and  lead.  Flint  glass,  tableware, 
optical  goods. 

Boro-silicon,  with  soda  and  lime.  Optical  goods, 
thermometer  tubes,  and  laboratory  ware. 

Boro-silicon  flint,  with  potash  and  lead.  Optical 
goods,  enamels,  imitation  gems,  etc. 

Borate  and  phosphate  glasses,  containing  no  silicon, 
for  certain  optical  purposes. 

Quartz,  pure.  Does  not  obstruct  the  passage  of  ultra- 
violet rays  as  does  all  other  glass,  and  is  not  broken 
or  cracked  by  sudden  changes  of  temperature. 

Glass  baking-dishes  are  coming  into  use,  first,  be- 
cause they  can  now  be  made,  and,  second,  because 


EVERYMAN'S    CHEMISTRY 

baking  takes  place  much  more  rapidly  in  these  than 
in  metallic  pans.  The  reason  is  simple  when  you 
know  it — metal  reflects  83  to  99  per  cent,  of  the 
radiant  heat  that  strikes  it,  while  glass  reflects  only 
3  to  14  per  cent. 

The  soluble  silicate  of  soda  is  called  "water  glass," 
and  is  used  for  making  bandages  for  broken  limbs,  and 
for  keeping  eggs  and  other  purposes. 

Glass  is  colored  by  means  of  certain  metallic  oxides. 
Ferric  (iron)  compounds  produce  green  color;  ferrous 
compounds  color  it  yellow.  Manganese  ranges  from 
amethyst  to  violet  color.  The  full  effect  is  produced 
only  when  the  manganese  is  fully  oxidized,  and  this 
takes  place  on  long  exposure  to  the  actinic  rays  of 
the  light.  Manganese  is  often  added  to  window  and 
other  glass  to  correct  the  green  color  from  iron  im- 
purities, and  the  violet  color  of  arc-light  glass  is  due 
to  the  oxidation  of  the  manganese  by  long  exposure 
to  the  light.  The  same  phenomenon  may  be  observed 
in  old  houses  in  Boston  and  in  Amsterdam,  Holland. 
Very  slight  quantities  of  cobalt  make  glass  blue. 
Iron  and  manganese  make  it  brown,  and  in  excess 
make  it  black.  Colloidal  gold  imparts  a  red  color  to 
it.  So  will  copper  if  larger  amounts  are  used,  but  it  is 
very  difficult  to  get  certain  results  with  copper. 

In  making  glass  it  is  always  necessary  to  use  some 
"cullet,"  or  broken  glass,  which  serves  as  a  flux  in 
the  glass  pots  or  tanks.  When  the  glass  is  made  there 
is  always  some  scum,  called  "glass  gall,"  that  floats 
on  the  top.  This  is  skimmed  off,  and  then  the  tem- 
perature is  allowed  to  cool  down  until  the  glass  is 
ready  for  blowing  or  casting. 

The  principal  product  of  the  American  glass  in- 
dustry is  building-glass,  of  which  there  are  three 
classes — sheet  (or  window),  plate,  and  wire -glass. 


SAND   AND    CLAY 

Four-fifths  of  the  window-glass  made  here  is  mechan- 
ically blown,  while  up  to  the  present  time  plate-glass 
is  always  cast.  In  the  near  future,  however,  owing  to 
improvements,  plate-glass  will  also  be  made  by  means 
of  blowing-machines.  The  difference  between  plate- 
glass  and  sheets  is  of  a  mechanical  rather  than  a 
chemical  nature.  Wire-glass  is  applied  in  structural 
work,  requiring  a  material  of  great  strength;  it  is 
especially  useful  in  factory  construction,  owing  to  its 
resistance  to  shock  and  its  fire-retarding  qualities. 

In  addition  to  building-glass  there  is  a  great  pressed 
and  blown  hollow- ware  industry.  This  includes  the 
tableware,  kitchenware,  and  bottle  industries.  Bot- 
tles of  all  sizes,  from  vials  to  carboys,  are  now  blown 
by  machinery.  The  development  of  the  automatic 
bottle-machine  revolutionized  the  industry. 

Not  long  ago  a  friend  asked  me  why  we  imported 
so  much  table  glassware,  the  finer  sorts  being  almost 
entirely  of  European  make.  The  answer  is  simple — 
we  haven't  the  skilled  labor.  But  the  reason  why 
we  have  not  the  skilled  labor  is  far  from  simple.  Let 
us  see,  however,  if  we  cannot  make  a  guess  at  it. 
When  a  man  achieves  sufficient  skill  to  make  glass- 
ware of  exceptional  beauty  he  must  have  sufficient 
taste  to  know  the  difference  between  that  which  is 
good  and  that  which  is  not  good;  he  must  be  enough 
of  an  artist  to  sense  beauty  when  he  has  it  before  him. 
If  he  is  only  a  hand  in  a  factory,  with  more  interest  in 
his  hours  and  his  pay  than  he  has  in  the  individual 
quality  of  his  work,  he  can  turn  out  good,  standard 
designs,  fair  enough  for  anybody  to  use,  but  he  will 
not,  because  he  cannot,  under  the  circumstances,  make 
exceptional  wares.  To  make  these  requires  an  artist, 
and  the  artist,  with  his  discriminating  taste,  finds  de- 
light in  the  thing  of  beauty  and  distress  in  that  which 


EVERYMAN'S    CHEMISTRY 

lacks  it.  He  enjoys  his  work  more  than  the  ordinary 
worker,  and  he  suffers  more  over  it.  One  day  is  not 
at  all  like  another.  In  making  glass,  for  instance, 
he  has  more  than  a  job;  he  has  a  profession.  Just  as 
the  physician  likes  to  succeed  with  a  difficult  case  and 
is  disappointed  if  his  methods  fail,  so  this  artist  worker 
gets  nervous  over  his  task  and  has  his  good  days  and 
bad  ones.  He  wants  good  pay,  and  he  gets  it,  but  he 
wants  a  great  deal  more.  He  wants  to  speak  his  own 
language,  he  wants  to  select  his  own  friends,  he  wants 
to  hear  his  good  work  praised,  for  comfort's  sake,  and 
he  wants  friendly  criticism  from  his  fellow-craftsmen. 
The  chances  are  he  has  never  heard  of  sanitary  plumb- 
ing, but  it  is  still  more  likely  that  he  tends  a  little 
flower-garden  and  has  a  favorite  spot  of  green  grass 
where  he  likes  to  lie  down  of  a  late  summer  afternoon. 
He  takes  himself  very  seriously  and  expects  others  to 
consider  his  individuality.  He  may  be  especially  fond 
of  a  local  brew  of  beer  or  a  mn  du  pays,  both  of  which 
may  injure  his  health,  but  it  is  impossible  to  per- 
suade him  that  it  is  so. 

That  seems  to  me  to  be  the  reason  why  we  keep  on 
importing.  At  the  same  time  I  think  it  fair  to  say  that 
in  cut  glass  the  product  of  the  United  States  is  equal 
to  that  of  any  country  when  the  makers  can  get 
potash  to  make  the  quality  desired.  The  work  of 
cutting,  however,  is  more  mechanical  and  less  artistic 
than  required  to  produce  other  ornamental  glass  ob- 
jects. Some  day  our  ornamental  glassware  may  equal 
that  of  France,  Saxony,  or  Bohemia.  This  will  be  when 
we  learn  how  to  deal  with  the  artistic  temperament. 
To  the  man  with  a  love  for  organization  and  a  sense 
of  order  the  artistic  temperament  offers  problems  to 
rack  his  very  soul. 

Now  let  us  return  to  our  chemical  muttons. 

140 


SAND   AND    CLAY 

Aluminium  or  aluminum,  as  it  is  often  called,  is  a 
metal  in  nearly  every  respect  except  that  the  hydroxide 
dissolves  alkalies  to  form  aluminates,  thus  acting  as  a 
very  mild  acid.  It  is  the  third  of  the  elements  in  the 
way  of  abundance  in  the  crust  of  the  earth.  It  is 
not  found  in  a  free  state,  owing  to  its  affinity  for  oxy- 
gen, and  until  the  hydro-electric  development  at 
Niagara  Falls  it  was  too  expensive  to  prepare  to  find 
general  use.  This  " silver  from  clay,"  as  it  has  been 
called,  is  now  produced  in  enormous  quantities  at 
Niagara  Falls  by  the  process  of  the  late  Charles  M. 
Hall,  which  he  worked  out  in  1886,  a  year  after  he 
graduated  from  Oberlin  College,  when  he  was  twenty- 
two.  Heroult,  a  Frenchman  of  about  the  same  age, 
and  also  a  brilliant  metallurgist,  devised  the  same 
process  at  about  the  same  time  in  France,  but  Hall 
had  the  advantage  of  a  little  time,  certain  practical  de- 
tails, and  the  further  convenience  of  backing  by  some 
Pittsburgh  millionaires.  So  Hall  had  the  pleasure 
of  seeing,  within  the  short  span  of  his  life,  the  price  of 
aluminium  fall  from  four  dollars  a  pound  in  1886  to 
eighteen  cents  a  pound,  and  of  being  the  man  who 
made  it  happen.  He  died  at  the  age  of  forty,  leaving 
a  fortune  of  many  million  dollars.  Heroult,  after 
Hall's  success,  addressed  himself  to  the  development 
of  the  electric-steel  furnace.  He  was  well  known  to 
American  chemists  from  his  frequent  visits  to  America, 
and  was  as  joyous  and  agreeable  a  companion  as  one 
is  likely  to  meet.  He  died  shortly  after  Hall. 

Very  fine  particles  of  aluminium  will  burn  to  the 
oxide  called  alumina,  A12O3,  in  an  atmosphere  of  oxy- 
gen, but  in  bars,  sheets,  or  wire  it  holds  well  in  the 
air  because  of  a  thin  film  of  alumina  which  is  formed 
on  the  surface.  This  alumina  is  found  in  a  mineral 
called  bauxite,  which  contains  50  to  70  per  cent. 

141 


EVERYMAN'S    CHEMISTRY 

of  A12O3,  and  is  mined  in  Georgia  and  Alabama  and 
in  France. 

Corundum  is  practically  pure  alumina,  and  is  one 
of  the  hardest  substances.  Emery  is  impure  alumina, 
and  contains  magnetite  and  hematite;  it  is  nearly 
black  in  color.  Both  corundum  and  emery  are  used 
as  abrasives. 

Now  just  as  we  found  silica,  SiO2,  to  be  the  chief 
ingredient  of  sand,  so  silicate  of  aluminium  is  the  chief 
ingredient  of  clay.  There  is  an  aluminium  chloride, 
A1C13,  which  is  an  unstable  compound,  but  which  is 
used  in  organic  chemistry.  Among  its  various  appli- 
cations it  is  found  useful  in  separating  gasolene  from 
heavier  bodies  in  crude  petroleums. 

Aluminium  sulphate,  in  the  form  of  a  double  salt  with 
an  alkali,  will  crystallize  with  a  great  deal  of  water  in 
the  crystals.  These  bodies  are  called  alums.  Ordinary 
alum,  that  we  know  as  a  mild  astringent  in  household 
use,  is  potassium  alum.  In  the  dyeing  industry  this 
is  being  superseded  by  aluminium  sulphate  and  so- 
dium aluminate. 

The  Hall  process  requires  alumina  for  the  manu- 
facture of  metallic  aluminium.  Indications  point  to 
the  discovery  of  a  more  economical  process  whereby 
the  metal  will  be  obtained  direct  from  the  silicate,  or 
clay.  Clay  is  the  generic  term  for  that  kind  of  earth 
composed  chiefly  of  silicate  of  aluminium.  It  is  never 
pure;  it  is  mixed  with  silica,  and,  although  a  reason- 
ably pure  silicate  of  aluminium  called  kaolin  is  white, 
there  are  not  many  white  clays.  Organic  matter, 
humus,  fossils,  shells,  limestone,  iron  as  sulphide  which 
makes  it  dark  blue  and  which  weathers  to  brown,  and 
oxides  of  iron  making  it  red  and  yellow,  are  some  of 
the  things  found  with  it.  And  since  clay,  when  finely 
enough  divided,  is  in  a  colloidal  state,  and  will  slip 


SAND   AND   CLAY 

through  almost  any  filter,  it  is  fair  to  say  that  the 
chemistry  of  clay  products  is  full  of  difficulties. 

Clay  has  the  property  of  being  soft,  coherent,  and 
plastic  when  wet,  and  when  dehydrated  one  of  the 
most  indestructible  of  substances.  Heat  will  not  then 
disintegrate  it,  chemically,  save  at  very  high  tem- 
peratures, and  it  does  not  take  on  water  to  go  back  to 
its  original  condition.  The  only  trouble  is,  as  every 
housewife  knows,  things  made  of  clay  will  break. 

To  make  brick,  clay  is  shaped  into  forms  and  fired. 
There  are  refinements  and  difficulties  in  the  handling 
of  materials,  but  we  shall  not  go  into  them.  Fire- 
brick requires  a  clay  very  low  in  iron  and  rich  in  silica. 

Pottery  is  a  clay  industry,  and  the  number  of  kinds 
of  clay  employed  in  it  is  legion,  but  in  effect  this 
large  number  is  due  to  the  very  many  kinds  and  quan- 
tities of  impurities  there  are  mixed  with  aluminium 
silicate.  To  make  flower-pots  is  no  more  of  an  art 
than  making  brick,  but  the  refinements  of  the  art 
reached  by  the  great  Chinese  potters  baffle  the  chem- 
ist. The  trouble  is,  the  reactions  all  take  place  at  such 
high  temperatures  that  Mr.  Chemist  cannot  be  there 
himself  to  find  out  what  happens.  If  he  could  only 
turn  into  a  " silicon  man"  and  spend  a  season  in  a 
pottery  kiln  and  a  cement  kiln,  he  would  have  enough 
material  for  any  number  of  Ph.D.  dissertations. 

When  clay  is  fired  it  becomes  hard  and  brittle. 
But  it  is  still  porous.  In  order  to  avoid  this  porosity 
and  to  make  it  easier  for  the  potters,  quartz  and  feld- 
spar are  added.  Now  the  less  such  admixtures  are 
present  the  more  difficult  the  porcelain  is  to  burn, 
but  at  the  same  time  the  less  sensitive  the  ware  is 
to  changes  in  temperature.  The  glaze  is  produced 
by  a  second  firing,  and  the  effect  of  the  process  is  to 
cover  the  earthenware  with  a  kind  of  glass.  In  com- 


EVERYMAN'S   CHEMISTRY 

mon  pottery  this  is  produced  by  introducing  salt, 
NaCl,  into  the  kiln.  The  hot  steam  causes  the  forma- 
tion of  hydrochloric  acid,  HC1,  and  sodium  hydrox- 
ide, NaOH,  which  unites  with  the  clay  to  form  sodium- 
aluminium  silicate — a  common  glass.  Every  type  of 
potters'  clay  has  its  own  type  of  glaze,  say  the  potters, 
although  with  any  good  type  of  plastic  clay  which 
cannot  be  fired  at  the  highest  temperatures  lead 
glazes  have  proved  practicable.  This  is  provided  by 
lead  oxide.  Putting  on  the  glaze  is  putting  a  coat  of 
glass  on  a  vessel. 

The  colors  are  applied  sometimes  before  the  first 
firing  and  sometimes  afterward,  but  before  glazing. 
They  are  mineral  colors,  of  course,  because  the  heat 
of  the  kiln  would  destroy  the  chemical  constitution  of 
organic  compounds. 

The  principal  varieties  of  clay  are : 
Clay,  the  term  by  which  aluminium  silicates  are  gen- 
erally known,  and  applies  to  those  not  otherwise 
classified. 

Ball  clay,  plastic  and  of  high  tensile  strength,  used  in 
making  porcelain  and  to  give  body,  for  instance, 
to  abrasive  wheels. 

China  day,  or  kaolin,  white,  consisting  almost  entirely 
of  hydrated  silicate  of  alumina.  Used  in  making 
chinaware,  as  a  filler  for  cotton  goods  and  paper, 
and  in  coating  book  and  wall  paper,  cloth  for  win- 
dow-blinds, in  paint  manufacture,  and  in  some 
floorings. 

Fire  clays.  These  differ  among  themselves,  but  are 
low  in  impurities,  such  as  lime,  magnesia,  iron 
oxide,  and  the  alkalies  which  are  fluxing  materials. 
Used  for  fire-brick  and  other  refractories. 
Pipe  clay,  plastic,  white,  and  relatively  high  in  silica. 
Used  in  making  porcelain  and  enamel- ware.  Also 

144 


SAND   AND    CLAY 

used  in  paint-making  as  a  depository  for  certain 
pigments.  Must  be  free  from  grit. 

Slip  day,  applied  to  a  clay  used  as  a  glaze  for  stone- 
ware. Is  high  in  fluxing  impurities  and  melts  to  a 
greenish  or  brown  glass. 

Stone  day,  usually  refractory  or  semi-refractory,  and 
vitrifies  without  losing  its  shape.  Must  have  good 
tensile  strength  and  be  plastic  enough  to  work  on  a 
potter's  wheel.  Used  for  the  body  of  stoneware. 

Feldspar.  In  discussing  potash  we  referred  to  feld- 
spar as  an  unlimited  source  of  supply,  provided  only 
the  potash  could  be  removed  from  it.  But  the 
mineral  has  other  uses,  as  you  shall  see.  It  is  a 
very  wide-spread  mineral,  although  often  found  in 
such  small  grains  mixed  with  other  rock  as  not  to 
be  available.  There  are,  however,  many  large 
deposits  of  it  which  may  be  easily  mined  and  sepa- 
rated. The  chemical  composition  is  about  as 
follows : 

Silica       (SiO2),    65  per  cent. 
Alumina  (A12O3),   18        " 
Potash     (K2O),     17        ". 

The  potash  is  sometimes  partly  and  sometimes 
wholly  replaced  by  soda.  The  spar  is  mined  and 
ground  usually  in  pebble-mills  lined  with  quartz 
and  using  flint  pebbles  to  avoid  contact  with  iron, 
for  the  chief  use  of  feldspar  is  in  the  ceramic  arts, 
and  the  presence  of  a  very  small  amount  of  iron 
will  affect  the  color.  In  the  body  of  porcelain  it 
fuses  during  the  firing  and  forms  a  firm  bond  be- 
tween the  particles  of  clay  and  quartz.  In  the 
glaze  it  fuses  and  forms  with  the  other  ingredients 
an  opalescent,  glassy  covering.  The  melting-point 
depends  upon  the  amount  of  alkalies  (potash  and 


EVERYMAN'S    CHEMISTRY 

soda)  it  contains;  the  more  alkali  the  lower  the 
melting-point,  and  as  potash  is  replaced  by  soda 
the  melting-point  goes  still  lower.  It  is  also  used 
in  making  enamels  for  brick  and  metals,  for  false 
teeth,  and  inferior  qualities  are  used  as  bonding 
materials  for  abrasive  wheels,  such  as  emery,  corun- 
dum, etc.  The  addition  of  alumina  to  a  glass 
mixture  makes  opalescent  glass;  and  as  feldspar 
contains  it  in  a  readily  fusible  form,  it  is  used  in 
making  opal  glass.  Very  finely  ground  feldspar  is 
used  in  preparing  certain  scouring  soaps  and  polishes. 

Fuller's  earth  is  a  clay  showing  no  specific  quality  in 
its  chemical  analysis,  but  appears  to  be  a  product 
of  the  degeneration  of  feldspar.  It  has  the  prop- 
erty of  absorbing  certain  substances,  and  it  is 
used  in  chemical  industry  for  clarifying  petroleum, 
lard,  cotton-seed,  and  other  oils.  Here  we  touch 
colloidal  chemistry  again. 

Mica  is  closely  related  to  feldspar  in  a  chemical  sense, 
being  a  class  of  minerals  consisting  of  silicates  of 
alumina  and  an  alkali.  Physically,  however,  mica 
behaves  something  like  asbestos.  It  is  very  re- 
sistant to  electricity  and  to  heat.  It  may  be  split 
into  thin  sheets,  and  is  used  as  insulating  material 
in  many  electrical  apparatus  as  well  as  for  stove 
windows,  furnace  peep-holes,  and  the  like.  Very 
finely  ground  mica  that  is  free  from  quartz  is  mixed 
with  heavy  grease  and  used  as  a  lubricant.  In 
order  to  produce  a  scintillating  surface  on  wall- 
paper, white  mica  is  ground  very  fine  under  water 
and  then  attached  to  the  paper  by  means  of  an 
adhesive.  It  comes  from  India. 

Boron  is  related  to  aluminium  in  the  periodic  table, 
and,  like  aluminium,  it  is  tri-valent.    It  goes  into  com- 

146 


SAND   AND    CLAY 

bination  very  much  as  aluminium  does,  but  here  the 
cousinship  ends.  Aluminium  is  a  metal,  but  boron  is 
not ;  in  a  free  state  (in  which  it  is  not  found  in  nature) 
it  is  a  brown,  amorphous  powder.  It  forms  an  oxide, 
B2O3,  which  is  the  anhydrid  of  boric  acid,  also  known 
as  boracic  acid;  the  two  expressions  are  names  for 
the  same  thing.  There  are  several  kinds  of  boric  acid, 
differing  only  in  the  number  of  molecules  of  water 
combined  with  the  boric  oxide,  B2O3,  but  we  shall  not 
consider  them  in  detail.  It  is  a  very  mild  acid. 

The  best  known  salt  is  borax,  which  is,  chemically 
speaking,  sodium  tetraborate,  Na2B4O7.ioH2O,  and 
this  is  mildly  alkaline,  because  the  sodium  pulls  harder 
one  way  than  the  boric  acid  does  in  the  other.  In 
this  form  boron  finds  its  greatest  use — in  the  glass 
industry,  as  a  preservative,  as  a  mild  antiseptic  in 
ointments  and  lotions,  in  soap,  as  a  cleansing  agent 
in  laundries,  for  soldering  (to  clean  metallic  surfaces), 
and  for  many  other  purposes. 


XIII 

LIME   AND   MAGNESIA 

Calcium  —  Lime  and  Mortar  —  Uses  of  Lime  —  Calcium  Salts  —  Bleach- 
ing-powder  —  Carbide  of  Calcium  —  Gypsum  —  Cement  —  Mag- 
nesium —  Uses  —  Its  Virtues  and  Its  Vices  —  Fixing  Nitrogen  with 
It  —  Why  Sea-water  May  Not  be  Used  in  Boilers  —  Meerschaum 
—  Asbestos  —  Talc  and  Soapstone. 


is  another  of  the  chief  constituent 
parts  of  the  earth,  it  being  fifth  in  the  order  of 
the  elements,  and  constituting  about  3^2  per  cent. 
of  the  crust  of  the  earth.  It  is  found  in  rocks  as  lime- 
stone, marble,  and  chalk,  and  in  coral  reefs,  all  of 
which  are  in  the  form  of  the  carbonate,  with,  of  course, 
impurities  added.  Dolomite  is  a  double  carbonate  of 
magnesium  and  calcium.  Whole  ranges  of  mountains 
are  composed  of  it.  As  the  phosphate  it  occurs  in  the 
phosphate  rocks  of  Florida,  South  Carolina,  and  else- 
where, so  valuable  for  fertilizer.  As  gypsum  or  the 
sulphate,  it  is  also  very  plentiful,  and  it  is  an  important 
base  in  the  greater  number  of  natural  silicates.  Sea- 
water  contains  calcium  salts.  The  bones  of  fish  and 
of  vertebrate  animals  and  the  shells  of  mollusks  are 
chiefly  calcium  phosphate.  Calcium  salts  are  always 
present  in  plant  tissues,  concentrating  mainly  in  the 
leaves.  It  enters  into  many  kinds  of  glass,  as  we  have 
seen,  and,  as  we  shall  see,  it  is  a  necessary  constituent 
of  cement  and  mortar, 

148 


LIME   AND    MAGNESIA 

In  a  pure  state  it  is  a  silver-colored  white  metal, 
soft  enough  to  be  cut  with  a  knife — but  not  so  soft 
as  sodium  or  potassium — and  it  may  be  broken  with 
a  blow,  which  shows  the  fracture  to  be  crystal- 
line. Gently  heated  in  the  air,  it  burns  with  incan- 
descence to  the  oxide  of  calcium,  or  quicklime,  CaO. 
If  metallic  calcium  is  heated  to  a  dull-red  heat  in  a 
current  of  nitrogen,  it  leaves  a  spongy  mass  that  con- 
tains nitrogen  in  combination.  It  fixes  both  nitrogen 
and  oxygen  from  the  air.  Here  we  have  a  very  simple 
way  of  getting  nitrogen  into  combination,  which  is 
so  much  wanted  and  which  requires  so  much  power 
to  accomplish  or  such  a  heavy  outlay  for  plant  to 
produce  ammonia  by  the  Haber  process.  The  only 
difficulty  is  to  get  the  calcium  out  of  the  abundant 
limestone.  As  yet  the  process  is  too  expensive. 

Fluorine  attacks  calcium  violently  at  ordinary  tem- 
peratures, but  the  other  halogens  do  not  combine  with 
it  until  heated  up  to  four  hundred  degrees.  There  is 
a  hydride,  CaH2,  which  is  a  white  solid,  which  de- 
composes with  the  liberation  of  hydrogen  in  the  pres- 
ence of  water. 

Lime  we  know  as  quicklime,  which  is  the  oxide 
CaO,  or  anhydrous  lime,  and  as  slacked  lime  or  calcium 
hydroxide,  Ca(OH)2,  or  amorphous  lime;  but  the  term 
is  loosely  applied  to  calcium  products  generally,  as 
limestone,  the  carbonate,  and  soda-lime  glass,  the 
double  silicate.  Let  us  first  consider  the  oxide,  or 
quicklime.  It  is  produced  by  heating  calcium  car- 
bonate in  one  form  or  another,  as  limestone,  marble, 
chalk,  etc.,  to  redness.  If  the  raw  material  contains 
clayey  matter — that  is,  aluminium  silicate — the  prod- 
uct is  more  of  a  cement  than  a  lime,  and  these  impuri- 
ties may  do  no  harm  for  building  operations,  which, 
as  we  know,  is  One  of  the  great  uses  of  lime.  On  the 

149 


EVERYMAN'S    CHEMISTRY 

other  hand,  if  the  raw  material  contains  magnesium, 
it  may  cause  serious  trouble  in  building,  as  the  mag- 
nesia hydrates,  or  takes  up  water  much  more  slowly 
than  lime,  and  this  may  take  place  after  the  mortar 
is  in  place.  Then  the  expansion  due  to  the  slacking 
of  the  magnesia  may  destroy  the  mason's  work. 

Did  you  get  this?  I  think  it  a  very  good  example 
of  the  cousinship  of  elements.  First  let  us  note  that 
mortar  is  a  mixture  of  sand  and  lime.  The  slacked 
lime  and  water  form  a  jelly-like  mass  which  is  stiffened 
by  the  sand.  Then,  when  the  water  evaporates,  the 
lime  hardens  and  becomes  much  stronger.  On  gradual 
exposure  to  the  air  the  carbonic-acid  gas  (CO2),  which 
is  always  present  along  with  moisture,  reacts  upon 
the  lime  or  calcium  hydroxide  and  forms  carbonate  of 
calcium  or  a  kind  of  limestone  mixed  with  the  sand. 
(Limestone  and  marble,  you  may  remember,  are  both 
of  them  carbonate  of  calcium.)  Limestone  is  better 
than  mortar;  it  is  stiffer  and  holds  better.  This  is 
proved  by  the  fact  that  good  mortar  becomes  stronger 
with  age. 

Now,  if  the  lime  contains  magnesia,  the  MgO  (mag- 
nesium oxide)  acts  like  lime  (CaO),  only  it  is  very 
much  slower.  Long  after  the  lime  has  been  slacked, 
the  mortar  made,  and  the  wall  built,  the  MgO  begins 
to  slack  and  swell  just  as  the  quicklime  did  when  the 
mason  first  put  water  on  it.  It  goes  through  the 
same  process,  several  weeks  or  even  longer  afterward — 
and  as  the  wall  gives  way  you  proceed  to  give  the 
mason  fatherly  advice.  Calcium  and  magnesium  do 
not  drive  well  in  double  harness;  they  have  such  en- 
tirely different  ideas  of  speed. 

The  other  great  use  for  quicklime  is  in  chemical 
manufacture.  Indeed,  lime,  either  as  quicklime  or 
slacked  (as  the  oxide  or  the  hydroxide),  is  probably  the 

150 


LIME   AND   MAGNESIA 

best  known  of  all  heavy  chemicals.  It  was  known 
to  the  ancients,  and  the  art  of  making  it  is  so  simple 
that  it  never  has  died  out  in  all  the  many  centuries 
of  ignorance  and  weariness  of  spirit  that  from  time  to 
time  have  fallen  upon  humanity.  Of  course  there 
are  refinements  in  manufacture,  and  special  kilns  are 
designed  with  occasional  saving  of  fuel;  but  there  is 
not  very  much  to  worry  over  in  the  making  of  lime 
from  limestone  except  to  keep  the  product  dry.  The 
graven  marble  images  of  the  heathen  gods  of  the 
Greeks  were  effectively  turned  into  this  raw  material 
for  mortar  by  the  pious  followers  of  the  Prophet.  We 
can  well  imagine  the  gusto  with  which  some  lovely 
head  of  Pallas  Athene  was  hurled  into  a  kiln — to 
make  the  mortar  to  stop  a  rat-hole  in  the  hut  of  a  goat- 
herd of  a  more  orthodox  if  not  a  more  enlightened  day. 
The  hydroxide  of  calcium  or  slacked  lime  is  the 
product  of  quicklime  and  water.  The  operation  is 
expressed,  chemically,  as  follows: 

CaO     +     H20     =     Ca(OH)2 
calcium        water        calcium  hy- 
oxide  droxide  or 

slacked  lime 

f. 

It  takes  place  with  liveliness  and  the  evolution  of 
considerable  heat.  Owing  to  this  thirst  for  water, 
lime  is  extensively  used  as  a  drying  agent. 

Lime  is  slightly  soluble  in  water;  more  so  in  cold 
than  in  hot  water,  which  we  may  put  down  as  one  of 
its  little  individualities.  Milk  of  lime  is  water  with 
more  lime  in  it  than  will  dissolve. 

Calcium  chloride,  CaCl2,  is  found  in  the  waters  of 
nearly  all  springs  and  rivers  and  in  the  sea.  It  seems 
as  though  nature  were  engaged  in  constantly  pro- 
ii  151 


EVERYMAN'S   CHEMISTRY 

ducing  more  and  more  calcium  chloride  and  letting  it 
be  carried  down  to  the  sea,  where,  in  the  course  of 
time,  as  we  have  noted  before,  calcium  chloride  and 
sodium  sulphate  seem  to  exchange  their  acids  and  be- 
come sodium  chloride,  or  common  salt,  and  calcium  sul- 
phate, or  gypsum.  Then  they  stay  there.  CaCl2  is  a 
by-product  of  a  number  of  chemical  processes,  especial- 
ly of  the  manufacture  of  soda  by  the  Solvay  or  am- 
monia process.  It  is  one  of  those  chemicals  that,  as 
noted  elsewhere,  is  still  looking  for  a  job,  the  only  gen- 
eral uses  being  that  of  keeping  roads  moist  in  dusty 
weather,  for  making  anti-freezing  mixtures,  and  other 
purposes,  none  of  which  demands  the  amount  that  is 
available.  It  has  an  intense  deliquescent  or  hydro- 
scopic  quality,  which  means  that  it  has  an  almost 
human  thirst.  One  hundred  parts  of  chloride  of  cal- 
cium, exposed  to  an  atmosphere  saturated  with  at- 
mospheric vapor,  will  absorb  124  parts  of  water  in 
ninety-six  days.  One  hundred  kilos  (220  pounds)  of 
Bavarian  man,  exposed  to  opportunity,  will  absorb 
more  than  124  kilos  of  beer,  which  is  over  90  per  cent, 
water,  in  less  than  ninety-six  days. 

Calcium  hypochlorite,  Ca(OCl)2,  may  be  prepared, 
but  bleaching-powder,  or  " chloride  of  lime,"  is  more 
interesting.  This  has  enormous  uses,  and  is  made 
by  allowing  chlorine  gas  to  act  upon  slacked  lime 
Ca(OH)2.  The  lime  is  spread  three  or  four  inches 
deep  on  perforated  shelves  in  large  chambers  and  the 
lime  raked  into  furrows.  Chlorine  is  led  through  the 
chambers,  and  the  reaction  proceeds  rapidly  at  first 
and  then  slows  down.  The  lime  is  occasionally  raked 
over  to  expose  fresh  surfaces,  and  after  standing  twelve 
to  twenty-four  hours  a  shower  of  lime  dust  is  blown 
into  the  chambers  to  absorb  the  excess  of  chlorine. 
The  result  is  not  calcium  hypochlorite,  Ca(OCl)2,  nor 

152 


LIME   AND   MAGNESIA 

is  it  chloride  of  calcium,  CaCl2.  It  was  supposed  to 
be  a  molecular  compound  of  both  CaCl2  and  Ca(OCl)2; 
but  this  is  not  likely,  because  the  chlorine  can  be 
expelled  from  it  if  carbon  dioxide,  CO2,  is  blown 
through  it,  and  calcium  chloride,  CaCl2,  will  not  give 
up  its  chlorine  to  CO2.  Then  calcium  chloride  is  very 
deliquescent — that  is,  it  absorbs  water,  and  bleaching- 
powder  does  not  do  this  to  any  appreciable  extent. 
It  is  not  calcium  hypochlorite,  as  proved  by  analysis, 
but  it  appears  to  be  chiefly  a  mixed  salt  of  the  formula 

/OCl 

C&--CI  or  CaOCl2.  With  it  is  some  slacked  lime, 
because  it  does  not  take  up  the  theoretical  amount 
of  chlorine — and  analysis  shows  this,  too. 

In  bleaching  fabrics  they  are  steeped  in  a  dilute 
solution  of  bleaching-powder,  which  is  not  wholly 
soluble,  leaving  some  lime  as  a  precipitate,  and  which 
shows  a  strong  alkaline  reaction.  Then  goods  are 
dipped  in  a  dilute  acid  solution,  and  washed.  The 
effect  of  this  alkaline  bath  and  subsequent  acid 
bath  upon  the  cellulose  of  the  fabrics  is  to  disturb  it 
chemically — and  oxygen  is  always  at  hand.  The 
oxygen,  so  to  speak,  sees  its  chance,  and  proceeds 
straightway  to  oxidize  the  cellulose  to  oxycellulose, 
which  is  an  amorphous  powder.  Then  we  say  the  cloth 
is  rotten,  and  complain  that  they  do  not  make  good 
materials  any  more. 

In  sanitation,  bleaching-powder  is  one  of  the  most 
effective  agents.  It  has  been  claimed  that  it  is  more 
effective  than  chlorine  gas,  but  modern  practice  seems 
to  take  to  free  chlorine,  when  it  can  be  used  con- 
veniently, in  preference. 

Calcium  carbide,  CaC2,  is  an  important  product 
made  by  heating  lime  and  coke  in  an  electric  furnace. 
The  reaction  CaO  +  3C  =  CaC2  +  CO  takes  place, 

iS3 


EVERYMAN'S    CHEMISTRY 

and  the  carbide  is  used  to  produce  acetylene  gas  for 
lighting:  — 


CaCz     +     2H2O     =     CaHz     +     Ca(OH)2 
calcium          water  acety-  slacked 

carbide  lene  lime 


The  high  temperature  of  the  electric  arc  is  needed 
to  make  the  calcium  carbide.  A  new  development  of 
the  carbide  industry  is  the  production  of  calcium 
cyanamide,  CaCN2,  or  nitrolime,  or  Kalkstickstojf,  as 
the  Germans  call  it,  meaning  chalk-nitrogen.  To  pro- 
duce it,  calcium  carbide  is  brought  into  contact  with 
nitrogen  gas,  obtained  by  the  distillation  of  liquid 
air.  They  are  maintained  at  a  heat  of  800°  to  1,000° 
for  a  time,  after  which  the  calcium  cyanamide  or 
nitrolime  is  found  as  a  coke-like  material.  This  is 
ground  to  powder  and  constitutes  one  of  the  great  new 
methods  of  bringing  nitrogen  into  the  soil.  The  art  of 
making  synthetic  ammonia  by  treating  CaCN2  with 
steam  we  discussed  under  the  subject  of  nitrogen. 

Calcium  phosphide  is  interesting  stuff.  It  is  made 
by  heating  lime  and  red  phosphorus  and  is  a  reddish 
brown  crystalline  body.  When  thrown  into  water  it 
instantly  decomposes  with  the  evolution  of  phos- 
phorated hydrogen,  which  is  spontaneously  combusti- 
ble. For  this  reason  it  is  used  to  make  signal-fires  at 
sea.  About  one  pound  is  placed  in  the  lower  half  of  a 
tin  can.  A  hole  is  jabbed  into  the  bottom  and  another 
into  the  top  of  the  can  before  it  is  thrown  overboard. 
The  can  is  supported  by  a  wooden  float.  Water  pene- 
trates the  lower  hole  and  the  gas  issues  from  the  upper 
outlet,  igniting  immediately  on  contact  with  the  air. 
It  burns  with  a  flame  from  nine  to  eighteen  inches 
high  and  lasts  about  half  an  hour. 

Calcium  sulphide,  CaS,  has  the  peculiar  quality, 


LIME   AND    MAGNESIA 

after  it  has  been  heated,  of  shining  in  the  dark  for  a 
time  after  exposure  to  light.  It  is  therefore  used  in 
the  manufacture  of  luminous  paints.  Zinc  sulphide 
has  the  same  property. 

Gypsum  is  calcium  sulphate,  and  so  is  plaster  of 
Paris,  CaSOi.  Gypsum  occurs  in  nature,  and  when 
a  part  of  the  water  with  which  it  crystallizes  is  driven 
off  it  is  called  plaster  of  Paris.  As  such  it  finds  its 
chief  uses  as  a  cement,  for  plastering  walls,  and  for 
the  reproduction  of  sculpture.  The  process  of  setting 
is  still  within  the  realm  of  theory,  and  we  shall  not 
try  to  solve  it.  Natural  gypsum  of  very  fine  texture 
and  having  a  translucent  quality  is  called  alabaster. 

By  cement  we  mean  calcareous  compounds  used  in 
building;  not  adhesives,  as  typified  by  glue.  A  brick- 
layer named  Aspdin,  of  Leeds,  England,  in  about  1845, 
calcined  a  mixture  of  chalk  (calcium  carbonate)  and 
clay  (aluminium  silicate)  and  found  that  the  product, 
when  ground  and  mixed  with  water,  would  set.  In 
other  words,  he  took  Thames  chalk  and  Medway  mud 
and  heated  the  mixture.  It  looked  like  a  building- 
stone  known  in  those  regions  as  Portland  stone,  and 
so  the  name  Portland  cement  arose.  While  engaged 
in  making  his  mixture  he  is  said  to  have  attired  him- 
self in  a  long  black  robe  and  the  pointed  cap  of  the 
necromancer  and  to  have  uttered  curious  incantations 
while  at  work.  He  had  a  tray  with  several  compart- 
ments, in  each  of  which  he  had  various  powders  which 
he  would  scatter  into  the  kiln  as  his  operations  pro- 
ceeded, and  he  accompanied  this  with  a  grand  display 
of  jargon  which  was  supposed  to  be  black  magic.  He 
had  also  a  neighbor  named  Johnson,  and  Johnson  was 
endowed  with  more  curiosity  than  belief  in  magic. 
He  discovered  that  the  magic  powders  on  Aspdin 's 
tray  were  powdered  sulphate  of  copper,  limestone, 


EVERYMAN'S    CHEMISTRY 

and  other  ingredients,  but  the  content  of  the  cement 
baffled  him.  It  also  baffled  the  chemist  whom  he 
employed  to  analyze  it,  for  he  came  to  the  conclusion 
that  it  was  calcium  phosphate.  So  Johnson  proceeded 
to  calcine  the  bones  of  animals  until  his  neighbors 
protested  against  the  lively  smell.  But  Johnson  con- 
tinued to  experiment  until  he  succeeded,  and  then  the 
industry  really  began. 

Portland  cement  is  the  most  important  of  all 
cements.  It  consists  of  compounds  of  lime  and  silica 
and  of  lime  and  alumina.  These  are  necessary,  but 
it  commonly  contains  other  compounds  of  lime,  with 
ferric  oxide,  magnesia,  insoluble  silicates,  some  sul- 
phates, and  then  some  more.  The  important  constitu- 
ents are  lime,  silica,  and  alumina  in  proper  propor- 
tions. These  bodies  exist  in  the  cement  in  the  form 
of  double  and  treble  salts — viz.:  tricalcium  silicate, 
3CaO.SiO2;  dicalcium  silicate,  2CaO.SiO2;  and  tri- 
calcium aluminate,  3CaO.Al2O3;  and  these  do  not  exist 
separately,  but  rather  in  a  solid  solution  in  the  Port- 
land-cement clinker.  They  are  not  definite  com- 
pounds, but  solid  solutions,  like  glass.  Just  what 
happens  when  cement  sets  is  not  very  well  determined, 
but  what  seems  probable  is  that  a  soluble  calcium 
aluminate  is  dissolved,  and  that  this  straightway  de- 
posits an  insoluble  hydrous  or  combined-with-water 
calcium  aluminate,  which  "sets." 

So,  to  make  cement,  one  proceeds  to  heat  in  a  kiln 
limestone,  marble,  chalk,  or  marl,  all  of  which  con- 
sist chiefly  of  aluminium  silicate.  There  is,  in  some 
localities,  "cement  rock,"  which  contains  lime  and 
clay  materials,  but  the  cement  made  from  this  mate- 
rial is  usually  inferior  in  quality.  The  reason  is 
simple:  if  you  grind  up  natural  rock  and  fire  it  you 
have  to  take  what  comes,  whereas  in  making  so-called 

156 


LIME   AND   MAGNESIA 

"Portland  cement"  the  proportion  and  the  purity  of 
raw  materials  are  under  constant  control,  and  a  much 
better  quality  of  cement  may  be  obtained. 

In  the  manufacture  of  Portland  cement,  the  usual 
proportions  are  about  one  part  of  clay  (aluminium 
silicate)  to  three  parts  of  calcium  carbonate  (lime- 
stone, etc.),  and  the  materials  are  thoroughly  dried  by 
heating  in  rotating  drums.  The  mixture  is  very 
finely  ground  and  is  fed  into  the  upper  end  of  long, 
rotating  cylindrical  kilns  set  on  an  inclined  plane  and 
lined  with  fire-brick.  A  very  hot  flame,  usually  ob- 
tained by  burning  coal  after  first  bringing  it  to  the 
condition  of  a  fine  powder,  is  forced  in  at  the  lower 
end.  During  the  passage  the  reaction  takes  place, 
and  just  before  the  product  reaches  the  tremendous 
temperature  of  its  melting-point  it  is  removed  from 
the  kiln.  It  is  called  cement  "clinker,"  and  it  is 
then  ground  to  a  fine  powder  and  packed  in  barrels, 
etc.,  with  the  warning  pasted  on  it,  "Keep  in  a  dry 
place." 

Natural  cements  do  not  require  so  much  heating 
as  the  Portland  variety. 

Another  very  good  cement  is  made  of  blast-furnace 
slag.  The  slag,  as  it  flows  in  a  molten  mass  from  the 
blast-furnace,  is  granulated  by  a  stream  of  water 
directed  against  it.  It  dries  quickly,  and  then  it  is 
ground  to  a  very  fine  powder.  Dried  slacked  lime  is 
added  to  the  powder  and  is  ground  up  with  it,  and, 
in  accordance  with  the  content  of  the  slag,  other  cor- 
rectives are  added.  Then  it  is  calcined.  The  trouble- 
maker is  magnesia,  MgO,  because,  as  we  noted  in 
treating  of  lime  and  mortar,  the  magnesia  is  tricky. 

Since  cement  will  set  without  the  presence  of  air, 
it  will  set  under  water  about  as  readily  as  it  will  any- 
where else. 


EVERYMAN'S    CHEMISTRY 

Cement  is  not  often  used  alone,  but  rather  in  con- 
junction with  sand,  gravel,  broken  stone  or  rubble, 
in  the  proportion  of  about  one  part  of  cement  to  four 
parts  of  rock  material.  A  good  concrete  of  this  sort 
will  stand  pressures  of  five  thousand  to  seven  thou- 
sand pounds  per  square  inch,  without  being  crushed. 
Walls  built  of  concrete  hold  better  if  reinforced,  as  the 
term  is,  with  twisted  steel  rods,  running  one  way  or 
crossed  when  the  concrete  is  poured  into  forms,  leav- 
ing the  rods  firmly  embedded  in  the  concrete. 

Eighty-seven  million  six  hundred  and  eighty-five 
thousand  barrels  of  Portland  cement  were  consumed 
in  the  United  States  in  1915.  All  parts  of  our  country 
are  now  well  supplied  with  mills  for  the  manufacture  of 
Portland  cement,  and  the  supply  of  raw  materials  is 
practically  inexhaustible. 

Magnesium  is  an  alkaline  metal  and  is  found  very 
wide-spread  in  nature,  usually  connected  up  as  a 
double  salt  with  some  other  metal.  It  is  not  found  in 
a  free  state  because  of  its  avidity  for  oxygen,  with 
which  it  combines  to  form  magnesia,  MgO.  In  time 
with  water  this  becomes  the  oxy hydrate  Mg(OH)2, 
and  again,  in  more  time,  the  carbonic  acid  of  the  air,  if 
it  can  get  at  it,  will  produce  the  carbonate.  Although 
in  a  pure  state  it  can  be  kept  exposed  because  it  be- 
comes coated  with  a  thin  crust  of  MgO,  the  oxygen 
will  surely  get  it  in  time. 

It  is  stable  enough  with  its  coating  of  the  oxide, 
provided  it  is  in  large  enough  pieces.  If  we  cut  the 
light,  silvery- white  metal  (which  pure  magnesium  is) 
into  thin  strips,  we  can  light  it,  and  it  will  burn  with 
an  intensely  luminous  flame  to  the  oxide  MgO.  For 
this  reason  it  is  used  for  fireworks,  for  shrapnel  trailers, 
to  show  where  the  projectiles  land,  and  for  illuminat- 
ing bombs  to  make  daylight  over  the  enemy's  works 

158 


LIME   AND    MAGNESIA 

and  trenches.  It  is  also  used  in  photography  for 
flash-lights. 

It  is  produced  by  fusing  minerals  containing  it  and 
making  a  separation  by  electricity.  Improved  meth- 
ods of  producing  magnesium  have  been  developed  in 
the  United  States  since  the  foreign  supply  was  shut 
off  by  the  war.  It  appears  very  likely  that  the  devel- 
opment of  these  processes  will  result  in  much  cheaper 
metallic  magnesium  than  we  ever  have  known  before. 
Its  uses  in  metallurgy  are  increasing  very  rapidly. 
Although,  as  we  have  observed,  slivers  of  it  will  burn 
easily,  larger  blocks  of  it  will  not,  and  when  it  is  al- 
loyed with  other  heavier  metals  this  hazard  is  entirely 
removed.  It  alloys  remarkably  well  with  aluminium 
and  with  other  metals  in  the  place  of  aluminium.  It 
machines  easily  and  well,  and  it  casts  beautifully. 
It  is  one-third  lighter  than  aluminium  and  over  twice 
as  strong,  so  that  the  prospect  of  reducing  the  weight 
of  high-speed  engines  for  air  work,  etc.,  and  at  the 
same  time  increasing  their  strength,  is  very  favorable. 
Steel-makers  find  it  valuable  for '  'scavenging,"  because 
a  little  magnesium  thrown  in  when  the  ingots  are 
cast  will  combine  with  the  air  that  may  be  bubbling 
through  and  likely  to  weaken  the  center  of  the  ingot 
by  not  getting  out  fast  enough.  That  it  will  combine 
with  the  oxygen  is  easy  enough  to  understand,  but  it 
does  more  than  that.  Magnesium  combines  with 
nitrogen  direct  to  magnesium  nitride,  Mg3N2,  at  white 
heat.  Here  would  be  another  way  to  fix  atmospheric 
nitrogen  except  for  the  cost  of  magnesium. 

We  have  considered  it  as  a  useful  metal.  As  the 
oxide,  magnesia,  MgO,  it  is  useful,  too,  but  also  one 
of  the  worst  of  nuisances.  We  have  already  referred 
to  it  in  this  connection  under  the  subject  of  lime,  with 
which  it  is  so  often  associated. 


EVERYMAN'S   CHEMISTRY 

On  the  other  hand,  magnesia  is  coming  into  fre- 
quent use  in  building  operations  for  making  fire- 
proof flooring,  where  the  process  is  kept  under  chem- 
ical control.  Various  salts  of  magnesium  are  also  used 
for  this  purpose. 

The  chloride  MgQ.2  is  important.  In  the  Solvay 
soda  process,  as  you  may  recall,  magnesia  may  be 
used  instead  of  lime  to  drive  the  ammonia  from  the 
ammonium  chloride.  The  reaction  is  the  same,  ex- 
cept that  we  have  as  a  waste  product  magnesium 
chloride  instead  of  calcium  chloride.  But  magnesium 
chloride  is  not  very  stable,  and  heat  will  drive  the 
chlorine  out  of  combination  with  the  magnesium.  So, 
on  heating  it,  the  chlorine  is  freed  and  saved,  while 
the  magnesium  oxidizes  at  that  temperature  to  mag- 
nesia, MgO,  and  is  used  over  and  over  again  on  the 
ammonium  chloride.  And  by  this  method  nothing  is 
lost. 

This  instability  of  magnesium  chloride  is  the  reason 
why  sea-  water  may  not  be  used  in  the  boilers  of  steam- 
ships. Sea-water  contains  it  in  considerable  quantity. 
The  heat  drives  out  the  chlorine,  which  takes  on 
hydrogen  from  the  water  and  becomes  hydrochloric 
acid,  and  with  free  muriatic  acid  in  the  boilers  we  do 
not  have  to  explain  what  would  happen.  Here  is  the 
reaction  that  takes  place: 


MgCl2     +    H20      =     Mg(  +    HC1 

NOH 

magnesium       water         magnesium         hydro- 
chloride         heated  basic  chloric 

and  con-          chloride  acid 

centrated 

Magnesium  chloride  is  very  deliquescent  —  that  is 
to  say,  it  is  hygroscopic,  which  means  that  it  is  ex- 

160 


LIME   AND   MAGNESIA 

ceedingly  thirsty  for  water.  It  is  magnesium  chloride, 
MgCl2,  in  common  salt  as  an  impurity  that  makes  it 
take  on  water  as  it  does. 

Magnesium  is  found  in  soils,  and  the  German  Potash 
Syndicate,  which  sells  a  fertilizer  of  mixed  potash  and 
magnesium  chlorides,  advertises  that  the  magnesium 
is  of  material  value  in  discouraging  the  development 
of  cut-worms  and  other  noxious  organisms  that  de- 
stroy plants.  We  live  and  learn. 

Serpentine  and  meerschaum  are  hydrated  disilicates 
of  magnesium.  Asbestos  is  an  anhydrous  silicate,  and 
is  found  in  large  deposits  in  Canada.  It  is  a  rock 
crystallized  in  long,  fine  fibers  of  a  silky  appearance 
which  may  be  easily  separated,  spun  into  yarn  and 
rope  and  woven  into  cloth.  Asbestos  is  not  affected 
by  heat  save  on  very  long  exposures ;  it  is  in  effect  non- 
combustible,  and  it  is  not  attacked  by  common  acids. 
It  is  widely  used  for  insulation  and  fire-resisting  pur- 
poses. 

Talc  and  soapstone  are  acid  meta-silicates  of  mag- 
nesium, or  H2O,  sMgO,  4SiO.  Finely  powdered  talc 
is  used  for  toilet-powder,  as  a  filler  and  coating  for 
paper,  for  cloth  window-shades,  as  filler  for  cheap 
toilet  soaps,  and  many  other  purposes.  Soapstone  is 
used  for  griddles,  stone  linings,  switchboards,  labora- 
tory table-tops,  furnace  linings  and  acid  tanks. 

The  mixtures  of  calcium  and  magnesium  in  min- 
erals is  so  persistent,  especially  as  carbonates,  that 
we  may  as  well  review  a  few  of  them. 

Calcite  or  calc  spar  is  calcium  carbonate,  and  is 
common  in  veins  as  well  as  being  one  of  the  most  wide- 
spread rock-forming  minerals. 

Magnesite  is  magnesium  carbonate,  and  occurs 
generally  as  a  decomposition  product  of  magnesian 
rocks. 

161 


EVERYMAN'S   CHEMISTRY 

Dolomite  is  a  mixture  of  calcite  and  magnesite. 

Limestone  is  a  sedimentary  rock,  and  when  pure  it 
consists  of  calcium  carbonate.  When  it  is  crystalline 
it  is  called  crystalline  limestone,  and  if  the  texture  is 
fine  it  is  called  marble. 

Chalk  is  a  soft,  powdery  white  variety  of  limestone. 
Finely  ground  chalk  from  which  the  impurities  have 
been  removed  is  called  whiting,  or  Paris  white. 

Calcareous  marl  is  clay  mixed  with  calcium  car- 
bonate. 


XIV 

IRON   AND   STEEL 

Chemical  Habits  of  Iron — Metallurgy — What  Happens  in  the  Blast- 
Furnace — James  Gayley's  Invention — Furnace  Gases — Wrought 
Iron — How  Steel  Is  Made — Bessemer,  Open  Hearth,  Crucible, 
and  Electric  Processes — Tempering — Special  Steels — Combina- 
tions of  Iron — Ores — The  Futurej 

ABOUT  5  per  cent,  of  the  crust  of  the  earth  is 
iron,  and  it  is  everywhere.  It  is  not  found  in 
a  pure  state  because  in  time  the  oxygen  will  get  it — • 
whether  it  watches  out  or  not.  No  kind  of  paint  or 
covering  is  absolutely  stable,  and  when  it  cracks  there 
come  the  oxygen  and  some  water  from  somewhere, 
some  time,  and  the  iron  turns  into  rust,  which  is  ore. 
All  the  iron  and  steel  now  manufactured  by  the  mill- 
ions of  tons  is,  cosmically  considered,  in  a  transient 
state.  It  is  bound  to  go  back  into  combination  in 
time,  and  most  of  it  as  ferric  oxide,  Fe2O3.  Only  in 
one  place  in  nature  do  we  find  it  in  quantity  free  and 
uncombined,  and  that  is  in  meteorites,  which  are 
dropped  down  upon  the  earth  out  of  the  empyrean. 
So  there  is  no  oxygen  up  there  in  the  blue  between 
the  stars. 

Iron  has  two  methods  of  combining — with  three 
hooks,  called  ferric  compounds,  and  with  two  hooks, 
called  ferrous  compounds.  It  occurs  most  freely  as  the 
oxides,  Fe3O4  and  Fe2O3,  and  as  the  carbonate,  FeCO3. 

163 


EVERYMAN'S    CHEMISTRY 

These  are  the  favorite  ores.  It  is  also  found  as  pyrites 
or  the  sulphide,  FeS2,  which  is  roasted  to  get  out  the 
sulphur  for  sulphuric-acid  works,  after  which  the  re- 
maining iron  with  its  impurities  is  available  ore  for 
blast-furnaces.  It  is  also  found  in  silicious  rocks,  in  the 
earth,  in  many  plants,  and  dissolved  in  water.  We 
also  have  a  little  of  it  in  our  own  make-up. 

Of  course  magnetite,  or  magnetic  ore,  is  not  pure 
Fe3O4,  and  neither  is  any  other  ore  pure.  If  there  is 
enough  of  the  oxides  or  carbonate  or  other  ferric  or 
ferrous  (iron  in  combination  with  three  hooks  or  two) 
compounds  the  ores  are  workable.  Too  much  silicate 
makes  it  hard  to  manage. 

Theoretically  the  metallurgy  of  iron  is  very  simple, 
but  in  practice  it  is  not  simple  at  all.  The  problem  is 
to  bring  the  iron  out  of  the  ore.  So  coal,  usually  in  the 
convenient  form  of  coke,  and  iron  ore  and  limestone 
are  brought  together  in  the  fiery  furnace,  and  air  is 
blown  in  so  that  a  very  high  temperature  is  produced. 
The  coal  is  burned  to  carbon  monoxide,  CO,  and  this 
combines  with  the  oxide  of  iron  in  the  ore  to  produce 
carbon  dioxide,  CO2,  and  sets  the  iron  free.  Let  us 
write  out  the  equation  : 


Fe2O3     +     3CO     =     2Fe     + 

Ore  carbon         Iron          carbon 

monoxide  dioxide 

The  iron,  being  the  heaviest  of  all  the  things  put  into 
the  furnace,  sinks  to  the  bottom  in  a  molten  state. 
But  a  great  many  things  have  been  happening  in  the 
mean  time.  The  iron  ore,  coke,  and  limestone  are  fed 
in  separate  layers.  Then  air,  which  is  blown  in  from  be- 
low to  feed  the  fire,  partly  burns  the  coke  to  producer 
gas,  CO,  and  this,  combining  to  CO2,  causes  heat  enough 

164 


IRON   AND    STEEL 

to  melt  up  and  generally  decompose  the  compounds 
in  the  furnace.  The  carbonic  acid,  CO2,  is  driven  from 
the  limestone  and  escapes.  The  calcium  from  the 
limestone  combines  to  make  double  salts  with  the 
silicates  which  are  sure  to  be  in  the  ore,  and  this  is 
a  sort  of  glass.  So  now  we  have  at  the  bottom  of  this 
long,  upright,  somewhat  egg-shaped  blast-furnace 
(with  the  big  end  at  the  bottom)  the  molten  iron  in  a 
cylindrical  extension  underneath  the  big  egg.  Above 
this  is  the  slag,  or  molten,  glassy  silicates  of  lime  with 
other  things  in  suspension  or  dissolved  in  it,  and  over 
that  are  the  layers  of  the  furnace  charge,  slowly 
moving  down.  The  bosh,  or  that  part  of  the  furnace 
where  the  sides  contract  suddenly,  provides  that  the 
pressure  upon  the  slag  is  not  very  great.  In  effect,  the 
pressure  is  only  that  of  a  cone  of  the  charge  imme- 
diately above  it.  Air  comes  through  from  the  bottom 
upward,  like  real  blazes.  The  heat  of  the  molten  iron 
is  too  great  for  oxygen  to  combine  with  it,  and  it  is 
protected  from  oxidation  from  above  by  the  covering 
of  the  molten,  glassy  slag. 

At  regular  intervals  the  blast  is  stopped  and  the 
furnace  is  tapped  to  let  off  the  slag  in  one  direction,  and 
from  another  tap,  lower  down,  the  iron  is  run  off  into 
molds.  When  it  cools  and  is  taken  from 'the  molds 
it  is  pig-iron.  The  slag  formerly  had  no  value  except 
to  fill  in  hollow  places,  as  rock,  but  now  it  is  used  to 
make  Portland  cement,  because  of  its  content  of  the 
silicates  of  aluminium  and  calcium.  For  reasons  ex- 
plained elsewhere,  no  magnesium  is  wanted  in  the 
slag  that  is  used  for  cement.  As  soon  as  the  iron 
and  slag  are  run  off  the  blast  goes  on  again,  and 
the  feeding  of  coke  and  ore  and  limestone  also 
continues. 

The  air  always  contains  moisture,  and,  as  we  have 

165 


EVERYMAN'S    CHEMISTRY 

observed  under  "Hydrogen,"  the  warmer  the  weather 
is  the  more  moisture  the  air  can  hold  in  suspension. 
For  many  years  it  was  observed  that  blast-furnaces 
behaved  better  in  winter  than  in  summer.  So  Mr. 
James  Gayley,  a  well-known  American  engineer,  con- 
ceived the  idea  of  refrigerating  the  air  before  it  was 
blown  into  the  furnace,  to  get  out  the  moisture.  He 
was  known  as  a  competent  engineer  and  a  man  of 
ideas,  but  the  wiseacres  shook  their  heads.  "Too 

bad  about  poor  Jim  Gayley, ' '  they  said.  ' '  He's , ' ' 

and  they  tapped  their  foreheads  and  shook  their  coun- 
tenances some  more.  "He  thinks  he  can  heat  a  blast- 
furnace with  an  ice-machine,"  was  a  characteristic 
comment.  And  their  wives  felt  very  sorry  for  Mrs. 
Gayley,  and  wondered  if  they  had  not  better  call  and 
see  if  they  could  help — and  find  out  something. 

The  Gayley  process  of  refrigerating  air  before  use 
in  blast-furnaces  saves  from  one  to  two  dollars  a  ton 
in  the  cost  of  pig-iron.  And  Mr.  Gayley  is  a  very 
prosperous  man.  Some  day,  maybe,  somebody  will 
discover  a  cheap  way  to  separate  water  into  its  oxygen 
and  hydrogen.  It  doesn't  seem  likely,  but  it  may 
come.  Then  the  burning  hydrogen  would  save  a  great 
deal  of  coal  and  the  oxygen  would  be  there  to  burn  it 
with.  Or  a  very  cheap  method  of  liquefying  air  may 
come  to  our  ken.  Then,  with  the  nitrogen  distilled 
off,  there  would  be  only  one-fifth  as  much  air  to  heat. 
And  yet  this  might  not  save  so  much,  because  that 
heated  nitrogen  that  goes  into  the  furnace  and  then 
comes  out  again  does  a  lot  of  good  work.  It  helps  to 
dry  out  and  pre-heat  the  ore  and  coke  and  limestone 
before  the  reaction  begins.  The  gases  escaping  at  the 
top  of  the  furnace  are  not  very  hot. 

Mr.  J.  E.  Johnston,  a  well-known  authority  on 
blast-furnace  practice,  has  computed  the  results  of 

166 


IRON   AND    STEEL 

using  a  blast  of  50  per  cent,  oxygen,  and  has  designed 
a  furnace  to  meet  the  situation  if  some  invention 
should  provide  us  with  50  per  cent,  oxygen  at  a  low 
cost.  It  looks,  after  all,  as  though  a  considerable 
saving  in  coal  would  be  effected  by  it. 

Furnace  gases  are  now  studied,  and  they  prove  an 
interesting  subject.  They  have  sufficient  heating 
value  to  drive  the  gas-engines  to  blow  the  blasts — 
and  then  some  more.  They  contain  pieces  of  coke, 
which  are  saved.  They  have  to  be  washed  before  they 
are  led  into  the  gas-engines  to  get  out  the  sulphur 
fumes,  which  would  play  hob  with  the  cylinders. 
They  contain  also  particles  of  potash,  as  sulphide, 
cyanide,  and  in  other  forms  in  suspension.  The  Re- 
search Corporation  is  working  on  the  problem  of  con- 
serving this  potash,  with  a  view  to  bringing  it  down 
by  electric  precipitation.  A  very  interesting  sugges- 
tion has  lately  come  from  Doctor  Cottrell  which  will 
be  tried  out  shortly.  It  consists  in  adding  high  potash 
feldspar  to  the  furnace  charge.  This  should  produce 
a  better  iron  by  making  it  more  free  from  sulphur, 
which  the  potash  should  carry  off  in  the  gases  as 
potassium  sulphide.  And  the  potash  might  then  be 
brought  out  of  the  gases  by  washing  and  electric  pre- 
cipitation. We  referred  to  this  in  the  introduction. 

Now  pig-iron  is  iron  all  right,  but  we  must  remember 
that  it  is  also  a  great  deal  more.  We  have  had  it  in  a 
liquid  state,  and  as  a  liquid  it  dissolved  some  things 
that  will  and  some  that  will  not  stay  in  solution  in  the 
cold.  Pig-iron  carries  a  high  percentage  of  carbon — 
from  3  to  5  per  cent.  Some  of  this  is  combined  with 
the  iron  as  iron  carbide,  Fe3C,  but  a  large  part  of  it  is 
scattered  through  the  metal  as  graphite,  in  flakes. 
Graphite,  as  we  shall  learn  when  we  come  to  carbon, 
is  an  allo tropic  form  of  that  element  and  is  just  the 
12  167 


EVERYMAN'S    CHEMISTRY 

thing  not  to  have  in  iron.  It  keeps  the  particles 
apart,  makes  the  iron  brittle,  and  it  does  not  do  any 
good  at  all.  Then  there  are  other  impurities  present, 
such  as  sulphur,  phosphorus,  and  silicon.  Silicon  has 
its  uses  when  it  is  needed,  but  sulphur  and  phos- 
phorus are  rarely  of  any  use  to  it,  and  each  of  them  is 
generally  an  infernal  nuisance — in  iron. 

When  pig-iron  is  melted  up  and  cast  into  molds,  it  is 
cast-iron.  Of  course  the  foundryman  should  know 
what  he  is  putting  into  his  cupola,  so  that  he  may  know 
also  how  his  product  will  behave  after  it  comes  into 
use.  Any  old  pig-iron,  or  "No.  2  Foundry,"  will  not 
take  care  of  the  foundryman's  problems  to-day. 

Steel  differs  from  cast-iron  in  two  particulars:  it 
contains  less  than  2  per  cent,  of  carbon,  and  what 
carbon  there  is  in  it  is  combined  with  iron  as  iron 
carbide,  Fe3C.  There  is  no  graphite  in  steel.  Gen- 
erally speaking,  the  higher  the  carbon  content  the 
softer  the  steel.  But  there  are  refinements  in  the 
form  in  which  the  carbon  exists  in  the  steel  which 
we  shall  discuss  when  we  come  to  tempering. 

Wrought-iron  is  also  free  from  graphite  and  its 
carbon  content  is  low,  as  low  as  a  low  carbon 
steel — from  >£  to  H  per  cent.  The  method  of 
manufacture  leaves  a  slight  proportion  of  slag,  from 
A  to  2  per  cent.  This  slag  takes  the  form  of  long 
threads  extending  through  the  iron  and  thus  gives 
to  wrought-iron  a  fibrous  structure  not  known  to 
steel.  To  make  wrought-iron,  pig-iron  and  ore  are 
heated  in  a  reverberatory  furnace,  and  the  puddlers 
work  it  with  rods  until  the  impurities  are  melted  or 
driven  out.  The  more  it  is  wrought  (or  worked  or 
hammered  or  rolled  or  pounded)  the  tougher  it  be- 
comes. 

To  make  steel,  boil  iron,  and  there  are  several  ways 

168 


IRON   AND   STEEL 

of  doing  it.  The  Bessemer  process  is  the  cheapest, 
and  the  worst.  The  molten  iron  is  run  from  the  blast- 
furnace into  a  ladle  instead  of  into  molds,  and  is 
poured  into  a  cylindrical  vessel  with  a  funnel-shaped 
top,  which  tips  on  its  axis.  This  is  called  a  converter. 
Air  is  blown  through  from  the  bottom.  This  blows 
out  the  graphite,  it  oxidizes  and  blows  out  the  sul- 
phur and  other  impurities,  the  remaining  carbon  is 
converted  into  carbon  dioxide,  and  we  have  a  much 
purer  iron.  At  this  point  a  special  iron  rich  in  carbon, 
manganese,  and  silicon  is  thrown  in.  The  carbon 
provides  that  which  is  needed  in  the  steel,  the  man- 
ganese prevents  the  formation  of  iron  oxides,  because, 
all  things  being  equal,  oxygen  likes  manganese  better 
than  iron,  and  the  silicon  is  said  to  prevent  the  forma- 
tion of  bubbles  or  blow-holes  in  the  ingots,  although  it 
makes  the  steel  more  brittle.  And  still  they  suffer 
from  blow-holes.  Then  the  converter  is  tipped  on 
its  axis  and  the  contents  run  into  great  molds.  These 
are  ingots.  Other  metals,  such  as  magnesium,  etc., 
are  sometimes  added  before  the  ingots  are  cast,  with 
a  view  to  taking  up  oxygen  and  boiling  away  with  it. 

The  Bessemer  process  is  a  very  rapid  one;  over 
twenty  tons  of  steel  may  be  converted  in  half  an  hour 
from  pig-iron  in  a  single  converter.  The  operation  is 
regulated  according  to  the  color  of  the  flame,  and  it 
is  beautiful  to  watch.  If  we  had  only  more  esthetic 
sense  and  understanding,  Bessemer  steel-mills  would 
be  great  show-places. 

One  trouble  with  the  process  as  designed  by  Sir 
Henry  Bessemer  was  that  with  the  fire-brick  lining  the 
phosphorus  was  not  driven  out.  Fire-brick  being 
chiefly  a  silicate  of  lime,  a  lining  made  of  them  is 
called  "acid,"  because  of  the  SiO2  in  them.  So  Besse- 
mer converters  with  an  "acid"  lining  are  good  only 

169 


EVERYMAN'S    CHEMISTRY 

for  converting  high-grade  iron,  with  a  very  low  phos- 
phorus content.  Bessemer  ore,  so  called,  is  that 
which  carries  very  little  phosphorus.  An  improve- 
ment over  the  acid  lining  has  been  devised  by  sub- 
stituting magnesium  and  calcium  oxides  for  fire-brick. 
With  this,  for  obvious  reasons,  so-called  basic  lining, 
the  phosphorus  may  be  more  completely  eliminated 
and  lower  grades  of  iron  may  be  used. 

But  the  Bessemer  process  does  not  make  a  pure, 
reliable  quality  of  steel.  It  is  used  for  rails  and  some 
structural  shapes  and  steel  castings,  but  what  with 
the  quick  work,  the  high  temperatures  not  under 
good  control,  and  the  general  slap-dash  of  the  process 
the  product  is  not  always  dependable. 

The  open-hearth  process  was  designed  by  Sir  Will- 
iam Siemens,  and  it  takes  nearly  as  many  hours  to 
convert  a  large  charge  of  iron  to  steel  as  the  Bessemer 
process  takes  minutes  to  convert  a  small  one,  but  it 
makes  better  steel.  The  charge  is  pig-iron,  iron  oxide 
(ore),  limestone,  and  scrap  iron  and  steel.  It  is  heated 
by  a  mixed  blast  of  air,  and  gas  is  blown  over  the 
saucer-shaped  furnace.  The  slag  is  separated  and  the 
steel  cast  into  ingots.  The  tendency  is  to  increase  the 
size  of  open-hearth  furnaces;  some  installations  with 
a  capacity  of  two  hundred  tons  each  are  in  successful 
operation. 

Later  practice  shows  economy  in  combining  the 
processes.  The  iron  is  first  treated  in  a  Bessemer 
converter,  and  then,  but  for  a  much  shorter  time,  in 
large  open-hearth  furnaces.  The  product  is  open- 
hearth  steel. 

The  good  old  prehistoric  way,  the  method  em- 
ployed by  the  Saracens  to  make  Damascus  blades  to 
destroy  the  unbelievers;  the  sword  of  the  Chinese 
executioner  who  cut  off  the  heads  of  his  victims  with 

170 


IRON   AND    STEEL 

such  skill  that  they  did  not  know  anything  had  hap- 
pened until  he  graciously  gave  them  a  pinch  of  snuff, 
and,  by  the  jerk  of  the  sneeze  which  followed,  they 
discovered  themselves  to  be  headless;  the  sword  of 
Siegfried  and  the  marvelous  Excalibur — all  these  must 
have  been  made  by  the  crucible  process.  By  this 
method  the  best  steels  and  those  of  special  contents 
are  made,  although  it  is  being  superseded  in  many 
places  by  the  electric  furnace.  The  crucibles  or  pots 
are  made  of  graphite  and  hold  about  a  hundred  pounds 
of  iron.  To  make  the  best  quality,  wrought-iron  bars 
are  melted  up  with  the  necessary  amount  of  carbon 
in  the  form  of  coke,  because  the  graphite  of  the  pots 
will  not  combine  to  produce  iron  carbide.  Often  the 
charge  is  open-hearth  or  Bessemer  steel.  Some  lime- 
stone is  added  to  make  a  flux  for  the  impurities,  and 
then  whatever  is  needed  is  added  to  make  the  steel 
just  what  the  buyer  wants.  The  operation  is  under 
constant  control,  but  of  course  it  is  expensive.  Never- 
theless, makers  of  machinery  are  beginning  to  demand 
the  very  quality  of  steel  for  each  part  of  their  machines 
that  will  best  serve  its  purpose  and  last  longest.  The 
discovery  of  special  steel  alloys  for  special  purposes  is, 
as  we  have  said  before,  becoming  one  of  the  sportiest 
features  of  applied  chemistry,  and  many  of  them  are 
made  in  crucibles.  Some  special  steels  are  made  in 
open-hearth  furnaces,  and  still  more  in  electric  fur- 
naces. 

The  electric  furnace  is  a  late  development,  whereby 
Bessemer  or  open-hearth  steel  may  be  quickly  re- 
fined to  very  high  grades.  The  steel  is  poured  into 
the  furnace  in  a  molten  state  and  two  carbon  (graph- 
ite) electrodes  are  dipped  into  it.  The  passage  of 
the  current  through  the  molten  iron  produces  great 
heat,  and  the  impurities  and  nearly  all  the  carbon  are 

171 


EVERYMAN'S   CHEMISTRY 

driven  off.  Carbon  is  reintroduced,  together  with 
whatever  else  is  needed  to  make  the  steel  desired, 
and  the  whole  operation,  with  furnaces  containing 
twenty  tons  and  more,  is  completed  within  two  hours. 
Electric  converters  are  supplanting  crucibles  in 
considerable  measure.  According  to  a  recent  state- 
ment of  the  chief  engineer  of  one  of  the  largest  auto- 
mobile companies — and  these  are  great  consumers  of 
special  steels — it  was  declared  that  they  prefer  steels 
made  in  electric  furnaces  to  those  made  in  crucibles. 
The  electric  converter  is  in  effect  a  different  way  of 
doing  the  same  thing  that  is  done  in  crucibles,  but  on 
a  much  larger  scale.  The  best  practice  of  to-day 
seems  to  point  to  steel  made  in  two  consecutive  stages 
direct  from  the  blast-furnace  without  cooling — first  in 
Bessemer  and  then  in  electric  converters.  This  pro- 
vides for  economy  and  quality  at  the  same  time. 

Tempering. — If  we  heat  a  high  carbon  steel  to  a 
high  temperature,  the  very  hard  iron  carbide  will  dis- 
solve in  the  iron,  and  we  have  a  solution  of  iron  car- 
bide in  iron.  Now  if  we  cool  it  suddenly  the  carbide 
will  not  have  a  chance  to  crystallize  out,  and  we  have 
a  cold  solid  solution  of  iron  carbide  in  iron.  This  is  a 
very  hard  steel,  but  it  is  too  brittle  for  most  purposes. 
So  let  us  heat  it  again,  but  not  to  so  high  a  temperature 
as  before.  Some  of  the  iron  carbide  will  come  out  of 
solution  and  will  stay  there,  leaving  the  mass  as  iron 
with  carbide  in  solution  mixed  with  some  carbide 
which  is  not  dissolved  in  it.  The  steel  is  then  not  so 
hard,  but  it  is  less  brittle.  This  is  tempered  steel, 
tempered  according  to  the  quality  we  want  it  to  have. 
Tempering,  of  course,  treats  the  steel  after  it  is  made, 
and  tempering  will  not  make  good  steel  out  of  poor 
material. 

172 


IRON   AND   STEEL 

We  have  spoken  of  the  many  kinds  of  steel  that 
may  be  produced  by  making  alloys  of  it  with  different 
metals;  we  shall  mention  only  a  few  of  them: 

Nickel  steel  contains  3  to  3^  per  cent,  of  nickel. 
It  is  very  hard,  very  elastic,  and  remarkably  ductile. 
It  is  used  for  armor  plate,  bridge  cables,  propeller- 
shafts,  etc. 

Chrome  steel,  with  2  per  cent,  chromium,  or  mixed 
with  nickel  as  chrome-nickel  steel,  is  hard  and  elastic 
when  suddenly  cooled.  It  is  used  for  projectiles,  for 
parts  of  automobiles  (as  are  many  other  special  steels), 
in  rock-crushing  machinery,  and  in  safes. 

Manganese  steel  contains  as  high  as  12  per  cent, 
manganese  and  i>£  per  cent,  carbon.  This  is  very 
hard,  no  matter  what  treatment  it  receives.  It  is  so 
hard  that  it  has  to  be  cut  with  emery-wheels;  tools 
break  on  it.  If  cooled  suddenly  it  becomes  ductile, 
and  if  cooled  slowly  it  becomes  brittle — the  very 
opposite  of  high  carbon  steel. 

Tungsten  steel  runs  from  5  to  10  per  cent,  tungsten, 
is  very  hard  at  high  temperatures,  and  is  called  "  high- 
speed" steel.  This  is  because  metal-cutting  tools 
made  of  it  may  be  run  at  a  high  rate  of  speed,  some- 
times so  fast  as  to  make  the  cutting  edge  red-hot,  and 
yet  the  steel  does  not  lose  its  temper.  For  the  same 
reason  it  is  also  sometimes  called  "  self  -tempering'* 
steel. 

Vanadium  steel  combines  elasticity  with  great 
tensile  strength. 

Copper  steel  is  a  late  discovery.  A  small  amount 
of  copper,  about  %  of  i  per  cent.,  in  the  steel  will 
keep  it  from  rusting  for  a  considerable  time.  While 
steel  alloyed  with  a  small  amount  of  copper  does  not 
become  rust-proof,  the  copper  acts  as  a  rust  retardant 
to  a  remarkable  degree.  Some  authorities  deny  this 


EVERYMAN'S    CHEMISTRY 

with  considerable  vigor,  but  it  seems  to  work,  never- 
theless. 

The  manufacture  of  steel  is  the  greatest  of  American 
industries,  and  when  we  consider  the  subsidiary  in- 
dustries built  up  around  and  about  it,  it  seems  to 
spread  over  everything.  At  the  time  of  the  present 
writing  the  United  States  is  producing  steel  at  the 
rate  of  40,000,000  tons  per  year. 

When  iron  is  exposed  to  moist  air  it  becomes  covered 
with  a  loose  coating  of  rust  which  is  approximately 
2Fe2O3.Fe(OH)3.  In  dry  air  the  reaction  does  not 
take  place.  Owing  to  the  double  life  that  iron  might 
be  said  to  lead,  being  bi-valent  at  one  time  and  tri- 
valent  at  another  time,  there  are  whole  series  of  fer- 
rous and  ferric  compounds.  The  oxides,  in  a  more  or 
less  impure  state  as  they  are  found  in  nature,  are 
known  also  by  their  mineral  names.  Thus  magnetite, 
which  is  strongly  magnetic,  is  Fe3O4.  It  is  hard,  black, 
and  of  metallic  luster. 

Hematite  is  ferric  oxide,  Fe2O3,  and  varies  in  color 
from  red  to  black  in  nature,  but  when  finely  ground 
it  is  usually  red.  This  is  Venetian  red. 

Limonite  is  a  hydrated  ferric  oxide,  2Fe2O3.3H2O. 
It  is  also  known  as  brown  hematite. 

Ocher  is  limonite  mixed  with  clay,  and  if  it  contains 
an  appreciable  quantity  of  manganese  it  is  brown 
and  called  umber.  These  oxides,  in  a  more  or  less 
pure  form,  are  very  largely  used  in  the  paint  industry, 
especially  hematite  and  ocher. 

There  are  ferrous  and  ferric  chlorides,  and  other 
salts  which  we  shall  not  mention  in  detail,  except  the 
ferrous  sulphate,  FeSO4,  which  crystallizes  with  seven 
molecules  of  water  and  is  known  as  green  vitriol, 
FeS04.7H20. 


IRON   AND    STEEL 

The  iron  and  steel  industry  touches  us  more  closely 
than  any  other,  and  as  wood  grows  scarcer  steel  is 
taking  its  place.  Where  steel  is  not  available  we  often 
use  Portland  cement,  which  is  sometimes  a  by-product 
of  iron,  since  it  may  be  made  from  many  slags. 

Occasionally  the  question  is  raised  how  long  the 
present  supplies  of  ore  will  last.  I  have  even  heard 
fears  expressed  that  civilization  itself  is  threatened 
with  the  exhaustion  of  iron  ores.  When  we  consider 
that  one  of  the  principal  uses  of  steel  from  1914  up 
to  the  present  writing  in  1917  has  been  to  destroy  life 
and  property  in  war,  it  makes  us  almost  doubt  the 
civilizing  influence  of  the  great  metal.  We  need  not 
fear,  however,  that  it  will  disappear.  There  are  vast 
supplies  of  iron  constantly  being  discovered,  and  con- 
stant advances  are  being  made  in  the  art  of  concen- 
trating ores  so  that  they  may  be  smelted  economically. 
By  means  of  modern  concentration  processes  it  is 
estimated  that  certain  deposits  in  New  York  and  New 
Jersey  alone  would  furnish  50,000  tons  of  60  per  cent, 
ore  per  day  for  100  years  and  still  not  be  exhausted. 
Then,  too,  Tennessee  and  other  Southern  States  have 
enormous  stores  of  usable  ore.  And  when  the  time 
comes  for  iron  to  be  scarce,  if  it  ever  does,  it  is  a  fair 
guess  that  aluminium  will  be  obtained  direct  from 
clay,  and  of  this  the  supply  is  as  nearly  inexhaustible 
as  anything  on  earth. 


XV 

MORE   METALS 

Copper,  Zinc,  Lead,  and  Tin — Copper  Ores — Flotation — Smelting  and 
Refining — The  Righteous  Wrath  of  Neighboring  Farmers — Cop- 
per Compounds — Alloys — Zinc  and  Its  Ways — Zinc  Ores — Pro- 
duction and  Use — Galvanized  Iron  and  Brass — Oxides  and 
Salts — Tin  and  Its  Tricks — Production  and  Use — Lead — Chem- 
ical Nature  and  Sources — Compounds — Production  and  Use — 
The  Storage  Battery— White  Lead 

OXYGEN  is  certainly  a  royal  and  imperial  per- 
sonage among  the  elements.  It  claims  nearly 
everything  and  gets  as  much  as  it  can.  An  example 
of  this  is  the  geological  position  of  copper.  There  are 
several  oxides  known,  of  which  the  most  important 
are  cuprous  oxide,  Cu2O,  which  occurs  in  nature  as 
cuprite  or  red  copper  ore,  and  cupric  oxide,  CuO, 
known  in  its  native  impure  state  as  melaconite  or 
black  copper.  But,  as  greater  depth  is  reached,  down 
below  the  old  water  level,  the  ore  has  probably  re- 
mained hidden  from  oxygen  and  we  are  more  likely  to 
get  the  sulphides.  It  is  a  salmon-red  metal,  which  is 
malleable,  is  a  good  conductor  of  heat  and  electricity, 
and  has  considerable  tensile  strength,  so  copper 
utensils  may  be  made  with  thinner  walls  than  those 
of  iron.  The  mineral  acids  dissolve  it  easily,  while  the 
weaker  organic  acids  have  little  corrosive  action,  and 
that  is  why  cooking  utensils  are  occasionally  made  of  it. 
Ammonia  dissolves  it,  and,  just  to  show  the  per- 

176 


MORE    METALS 

versity  of  nitrogen  in  all  its  ways,  instead  of  behaving 
as  a  base,  as  it  usually  does,  it  behaves  as  an  acid. 
This  seems  to  be  the  body  formed,  which  is  called 
cuprammonium,  and  is  not  known  out  of  solution: 
Cu(NH3)4(OH)2.  It  is  a  safe  rule  never  to  bet  on 
what  ammonia  will  do  in  a  given  situation — unless 
you  happen  to  know.  Analogy  is  a  will-o'-the-wisp 
in  reasoning  with  ammonia.  On  the  other  hand,  there 
doesn't  seem  to  be  any  nitride  of  copper — a  combina- 
tion of  nitrogen  with  copper  and  nothing  else,  as  there 
is  a  nitride  of  magnesium. 

The  process  of  mining,  smelting,  and  refining  of 
copper  is  an  enormous  industry,  and  we  shall  take 
only  a  short  glance  at  it.  Most  of  the  copper  ore 
smelted  is  in  the  form  of  sulphides,  and  there  are 
always  other  metals  present  with  it;  but  in  many 
lean  ores  smelting  is  preceded  by  concentrating  in 
one  way  or  another,  and  of  these  the  process  of  flota- 
tion is  so  interesting  that  we  shall  have  to  describe  it. 

It  consists  in  grinding  the  ore  to  a  powder  and 
then  feeding  it  into  a  tank  containing  water  and  a 
slight  amount  of  oil.  As  bubbles  are  caused  to  rise 
in  the  water,  by  splashing  it  with  ladles  or  feeding  in 
compressed  air,  the  metal-bearing  particles  attach 
themselves  to  the  bubbles  and  float  to  the  top,  while 
the  lighter  gangue  of  limestone  or  other  rock  falls  to  the 
bottom.  The  phenomenon  is  regarded  as  due  to  the 
fact  that  the  oil  wets  the  metallic  surfaces  and  also 
the  surfaces  of  the  bubbles,  which  carry  the  oil  and  the 
metal  to  the  top.  The  particles  of  rock,  on  the  con- 
trary, not  being  wetted  by  the  oil,  do  not  attach  them- 
selves to  the  bubbles  and  so  fall  to  the  bottom.  By 
this  means  a  20  per  cent,  concentrate  may  be  obtained 
from  a  2  or  3  per  cent.  ore.  The  process  has  come 
into  very  wide-spread  use. 

177 


EVERYMAN'S    CHEMISTRY 

By  burning  out  the  sulphur  the  smelter  owners 
were  formerly  in  sore  straits  because  the  sulphurous 
fumes,  SOz,  did  not  provide  for  the  enjoyment  of  this 
life,  or  even  a  pleasant  intimation  of  the  future  in 
their  respective  neighborhoods.  Farmers  lost  their 
crops,  their  cattle,  their  tempers,  and  their  milk  of 
human  kindness  if  they  chanced  to  be  neighbors. 
The  situation  was  remedied,  as  we  have  explained  on 
another  page,  by  Doctor  Cottrell's  process  of  the 
electrical  precipitation  of  suspended  particles,  and 
permitting  the  sulphurous  gas  to  escape  hot  through 
the  high  stacks  and  thus  diffuse  itself  and  blow  away. 

There  are  two  methods  of  smelting  copper  ores  in 
vogue :  in  blast-furnaces,  which  are  upright  and  con- 
structed a  little,  but  not  very  much,  like  small  iron 
blast-furnaces;  the  second  method,  in  reverberatory 
furnaces,  accomplishes  the  same  thing  in  horizontal 
structures  in  which  the  fuel  is  burned  in  a  separate 
compartment  from  the  ore,  whereas  in  a  blast- 
furnace they  are  mixed.  The  task  accomplished  is 
the  separation  of  the  ore  into  what  is  known  as  copper 
matte  and  slag.  Now  matte  is  cuprous  sulphide, 
Cu2S,  and  iron  sulphide,  FeS,  in  varying  proportions, 
and  the  next  step  is  to  convert  the  matte  into  crude 
copper,  which  is  accomplished  usually  by  melting  it 
and  blowing  air  through  it  somewhat  as  in  a  Bessemer 
steel  converter.  Indeed,  the  process  is  called  Besse- 
merizing,  and  the  apparatus  is  known  as  a  converter. 
Copper  and  some  iron  are  left,  and  the  sulphurous 
fumes  escape  again,  only  to  be  disposed  of  or  to  make 
trouble.  Then  we  have  a  crude,  impure  copper,  which 
needs  to  be  refined.  It  is  cast  into  plates  and  these 
are  suspended  as  electric  poles  in  a  bath  of  copper 
sulphate  (CuSO4)  and  sulphuric  acid.  Very  thin  sheets 
of  pure  copper  form  the  opposite  poles,  and  the  cur- 

178 


MORE   METALS 

rents  of  electricity  are  started  through.  What  hap- 
pens is  that  the  sheets  of  pure  copper  are  electro- 
plated with  the  copper  that  comes  from  the  sheets 
of  crude  copper  until  the  crude  sheets  are  eaten  away 
and  all  of  their  copper  has  left  its  estate  of  impurity 
and  gone  over  to  abide  in  a  state  of  grace  on  the  op- 
posite poles. 

The  impurities,  of  which  there  are  many,  go  partly 
into  the  solution  and  fall  partly  as  slime  at  the  bot- 
tom of  the  apparatus.  Arsenic  and  antimony,  both 
of  which  are  likely  to  be  present,  do  both.  Bismuth 
is  precipitated  out  as  its  basic  salt.  Gold,  silver, 
platinum,  selenium,  and  tellurium  are  not  dissolved 
by  the  solution  and  drop  to  the  bottom  of  the  tanks 
as  a  mud  or  slime,  from  which  they  are  partially  re- 
covered. Nickel  and  cobalt  pass  into  solution  and 
are  not  plated  out  so  long  as  there  is  dissolved  copper 
present. 

There  are  many  salts  of  copper,  and  they  are  widely 
used.  Copper  chloride,  CuCl2,  is  one  of  those  thirsty 
chlorine  salts.  If  it  is  dried  in  vacuo  it  is  pale  blue. 
If  crystallized  out  of  a  solution  it  takes  with  it  two 
molecules  of  water  (CuCl2.2H2O)  and  forms  beautiful 
grass-green  needles.  It  is  a  powerful  disinfectant,  and 
is  also  used  in  calico  printing  as  well  as  in  chemical 
processes.  This  is  more  properly  known  as  cupric 
chloride;  the  cuprous  chloride,  in  which  copper  is 
monovalent,  CuCl,  is  also  known. 

Copper  sulphate,  CuSO4,  is  a  white  powder,  but 
crystallized  with  five  molecules  of  water  (CuSO4.5H2O) 
it  is  known  as  blue  vitriol  and  has  many  uses,  as,  for 
instance,  in  calico  printing  and  dyeing.  It  is  used  to 
prevent  rot  in  timber.  Farmers  soak  seeds  for  some 
hours  in  a  weak  solution  twenty-four  hours  before 
sowing,  to  prevent  smut.  It  is  applied  to  grape-vines 

179 


EVERYMAN'S   CHEMISTRY 

in  10  to  20  per  cent,  solutions  to  kill  fungous  growths. 
Large  quantities  are  used,  although  but  very  little  is 
needed  at  a  time,  to  kill  algae  and  other  vegetable 
growth  and  scum  in  lakes  and  ponds. 

Copper  silicide  is  made  by  fusing  copper  and  silicon 
in  an  electric  furnace  at  a  very  high  temperature. 
It  is  called  cuprosilicon,  and  is  silvery  white,  with  a 
metallic  luster,  and  is  hard  and  brittle.  It  is  used  for 
hardening  copper  and  to  add  to  tin,  zinc,  and  alu- 
minium bronzes  to  increase  their  tensile  strength  and 
hardness. 

The  carbonate  has  never  been  prepared  in  a  pure 
state,  but  compound  bodies,  such  as  malachite,  which 
is  copper  carbonate  and  copper  hydroxide,  crystal- 
lized together  Cu2(OH)2CO3,  and  azurite,  which  is 
Cu3(OH) 2(CO3) 2,  are  found  in  nature.  These  minerals, 
when  ground,  form  fine  but  expensive  green  paints. 

ALLOYS    OF    COPPER 

Brass  contains  1 8  to  40  per  cent,  of  zinc  and  melts 
at  a  lower  temperature  than  does  copper.  Its  great 
merit  is  its  resistance  to  oxygen  and  its  good  mechan- 
ical qualities.  A  variety  made  with  but  little  zinc 
may  be  beaten  into  very  thin  sheets,  and  is  called 
Dutch  metal.  Bronze  contains  3  to  8  per  cent,  of 
tin,  ii  or  more  per  cent,  of  zinc,  and  some  lead,  the 
rest  being  copper.  Until  iron  and  steel  were  brought 
into  use,  bronze  was  the  metal  used  for  weapons, 
tools,  and  castings.  For  works  of  art  it  is  highly  prized 
because  of  its  fusibility,  its  color,  and  the  beautiful 
patina  which  covers  it,  due  to  surface  corrosion. 

Gun-metal  contains  10  per  cent,  and  bell-metal  25 
per  cent,  of  tin. 

German  silver  contains  19  to  44  per  cent,  of  zinc 

1 80 


MORE    METALS 

and  6  to  22  per  cent,  of  nickel.  Aluminium  bronze 
contains  5  to  10  per  cent,  of  aluminium,  and  looks  like 
gold  in  color.  Silicon  bronze  contains  about  5  per 
cent,  of  silicon.  It  has  less  conductivity  than  pure 
copper,  but  is  twice  as  tenacious,  and  is  used  for  over- 
head electric  wires.  Phosphor  bronze  is  about  90 
per  cent,  copper,  9  per  cent,  tin,  and  i  per  cent,  or 
less  of  phosphorus.  Manganese  bronze,  for  ships' 
propellers,  contains  30  per  cent,  of  manganese. 

ZINC  is  always  bivalent — that  is,  it  has  two  bonds 
for  combining.  It  is  a  bluish  white  metal,  used  very 
widely.  It  is  a  part  of  brass,  in  which  it  serves  the 
purpose  of  stiffening  and  hardening  the  copper  and 
tin  with  which  it  is  alloyed.  Chemically,  it  will  be 
electropositive  or  electronegative,  according  to  the 
company  it  is  in.  If  the  company  is  very  negative, 
more  so  than  the  zinc,  it  will  be  positive,  and  vice 
versa.  Most  of  its  compounds  are  what  we  should 
expect  of  it  as  a  metal,  such  as  sulphate  of  zinc 
(ZnSO4) ,  chloride  of  zinc  (ZnCl2) ,  etc. ;  but  along  with 
a  very  positive  radical  it  will  turn  negative,  its  oxide 
will  act  as  an  acid  and  produce  zincates,  like  zincate 
of  sodium  and  a  few  others. 

It  changes  its  nature  according  to  the  temperature — 
according  to  the  weather,  we  might  say.  Pure  zinc, 
cold,  is  brittle.  At  I2o°-i5o°  centigrade  it  may  be 
rolled  into  thin  sheets  between  heated  rollers,  and  it 
will  then  retain  its  pliability  when  it  becomes  cold. 
At  2oo°-3oo°  centigrade  it  becomes  brittle  again,  and 
at  418°  centigrade  it  melts.  At  916°  centigrade  it 
boils. 

It  is  reasonably  permanent  in  the  air  because  there 
is  formed  a  layer  of  zinc  oxide  upon  the  surface,  which 
covers  it.  Mineral  acids  attack  zinc,  liberating  hydro- 

181 


EVERYMAN'S    CHEMISTRY 

gen  except  when  the  metal  is  pure.  Then  the  reac- 
tion does  not  proceed,  because  little  bubbles  of  hy- 
drogen cover  the  surface  of  the  zinc  and  protect  it 
from  the  surrounding  acid.  If  the  zinc  is  impure,  or 
if  a  platinum  wire  or  a  less  positive  metal  is  brought 
into  contact  with  it  in  the  fluid,  the  bubbles  of  hydro- 
gen leave  the  zinc,  touch  the  other  body,  and  fly 
away  into  the  air. 

It  occurs  in  nature  as  the  sulphide  known  as  zinc- 
blende,  as  the  silicate,  and  as  franklinite,  which  is  a 
composite  mineral  compound  of  zinc,  iron,  and  man- 
ganese oxides.  The  predominant  mineral  is  the  sul- 
phide, and  it  is  one  of  the  leading  raw  materials  in 
the  production  of  sulphuric  acid.  The  sulphur-free 
ore  is  then  heated  in  retorts,  producing  first  a  dust 
composed  of  zinc  and  zinc  oxide,  and  finally  molten 
zinc.  This  is  called  spelter,  and  contains  lead,  ar- 
senic, cadmium,  and  iron,  because  these  metals  are 
always  present  in  zinc-blende.  Electrolytic  refining 
of  zinc  has  lately  been  introduced.  Over  1,000,000 
tons  of  spelter,  or  crude  zinc,  are  consumed  in  the 
world  annually,  and  of  this  amount  about  300,000 
tons  constitute  the  American  consumption. 

Aside  from  its  use  in  brass,  it  is  used  as  sheets, 
often  in  preference  to  lead,  for  roofs,  gutters,  and 
architectural  ornaments.  Cleaned  sheets  of  steel 
dipped  in  molten  zinc  become  covered  with  it,  "gal- 
vanized," as  the  expression  is,  and  this  protects  the 
iron  from  rust  in  two  ways:  it  provides  an  air-tight 
covering  for  a  while,  and  even  when  the  zinc  is  weath- 
ered down  it  seems  to  rust  in  place  of  iron — that  is, 
the  iron  does  not  rust  until  all  the  zinc  is  oxidized. 
This  is  different  from  copper,  which  encourages  cor- 
rosion if  in  contact  with  iron  or  zinc,  and  yet,  as  we 
observed  under  iron,  %  of  i  per  cent,  of  copper 

182 


MORE    METALS 

alloyed  with  steel  seems  to  decrease  corrosion  300  to 
400  per  cent.  Please  excuse  me  for  not  explaining  this. 
Brass,  which  is  composed  of  metals  of  opposite  elec- 
trical properties,  seems  to  be  nearly  electrically  neu- 
tral toward  iron,  unless  it  is  a  red  brass,  in  which 
copper  predominates. 

Zinc  oxide,  ZnO,  is  very  widely  used  as  a  paint, 
sometimes  mixed  with  white  lead  and  often  in  sub- 
stitution of  it.  It  does  not  chalk  off  as  lead  does, 
and,  on  the  other  hand,  it  has  not  the  full  body.  It 
is  called  zinc-white  or  Chinese-white.  Artists  use  it 
in  connection  with  vermilion,  because  that  is  a  sul- 
phide of  mercury,  and  if  brought  into  contact  with 
white  lead,  the  sulphur  prefers  it  to  the  mercury,  and 
so  sulphide  of  lead  is  formed,  which  is  a  dirty  black 
smudge  instead  of  the  beautiful  red.  This  is  why 
many  beautiful  paintings  have  gone  off  in  quality  and 
lost  all  their  reds,  which  were  made  of  sulphide  of 
mercury  mixed  with  white  lead.  Now  the  sulphide 
of  zinc  is  white,  and  if  any  of  it  is  formed,  which  is 
not  likely,  from  contact  with  mercury,  the  red  may  be- 
come a  little  lighter,  but  that  is  all.  But  the  prefer- 
ence is  usually  for  white  lead  if  other  colors  will  stand 
it,  because  of  its  greater  body.  A  producer  of  zinc- 
white,  however,  may  deny  this  with  vigor,  and  call 
you  hard  names  if  you  say  so. 

Zinc  chloride,  ZnCl2,  is  used  as  a  caustic,  as  in  the 
presence  of  water  it  liberates  hydrochloric  acid: 

ZnCl2  +  H2O     =     HC1  +  Zn(OH)Cl 

zinc  oxy- 
chloride 

Solutions  of  it  are  used  to  impregnate  wood,  especially 
railway   ties,  to   prevent    the   growth   of  organisms 
which  cause  decay.     It  is  also  used  to  dissolve  the 
13  183 


EVERYMAN'S    CHEMISTRY 

oxides  (rust)  from  surfaces  which  are  to  be  soldered. 
The  equation  given  above  shows  how  hydrochloric 
acid  is  liberated,  which  does  the  work.  Like  all  salts 
of  zinc,  the  chloride  is  astringent  and  poisonous. 
"Barnett's  Disinfecting  Fluid,"  so  called,  is  a  solu- 
tion of  zinc  chloride. 

Zinc  sulphate,  ZnSO4,  is  a  white  salt,  known  also  as 
white  vitriol.  It  is  used  in  industry  and  in  medicine 
for  external  applications.  A  Y%  per  cent,  solution  is 
used  in  certain  eye  affections. 

TIN. — If  the  elements  had  consciousness,  tin  would 
need  a  group  of  eminent  counsel  to  defend  it  from 
charges  of  irregularity.  It  has  two  methods  of  com- 
bining— with  two  bonds  and  with  four.  As  tin,  tinnic, 
and  tinnous  compounds  did  not  sound  just  right  to 
the  chemical  authors,  or  possibly  they  did  not  know 
whether  to  spell  the  adjectives  with  one  "n"  or  two, 
they  took  the  Latin  word  stannum  and  made  their 
adjectives  of  that.  Stannous  compounds  are  of  tin 
with  two  bonds,  while  stannic  compounds  indicate 
that  four  bonds  are  engaged. 

Tin  is  addicted  to  allotropy  in  the  worst  way.  It 
is  a  silver-white,  crystalline  metal  of  low  tenacity 
but  great  malleability  under  ordinary  conditions.  It 
also  retains  its  luster  on  exposure  to  the  air.  It  is 
soft  enough  to  be  cut  with  a  knife  but  harder  than 
lead,  while  not  so  hard  as  zinc.  Despite  its  great 
ductility,  which  is  greatest  at  about  100°  centigrade 
(the  boiling-point  of  water),  it  grows  brittle  enough 
to  be  pulverized  when  it  has  been  heated  up  to  200°. 
If  a  bar  of  tin  is  bent,  it  emits  a  low,  crackling  noise, 
called  the  "tin  cry,"  said  to  be  due  to  the  rubbing 
of  the  crystal  faces,  one  upon  the  other.  It  has  a 
great  disposition  to  crystallize  on  solidification  into 

184 


MORE    METALS 

two  different  forms  of  crystals  according  to  conditions, 
tetragonal  and  rhombic. 

Now  if  this  same  tin  is  cooled  to  a  low  temperature 
it  will  crumble  to  a  gray  powder.  This  takes  place 
very  slowly  at  ordinary  cold-weather  temperature,  but 
is  likely  to  proceed  very  rapidly  at  —48°  centigrade. 
At  temperatures  lower  than  this  the  crumbling  slows 
down.  Organ  pipes  and  roofs  have  been  observed  to 
go  to  pieces  from  this  "tin  pest,"  or  "tin  disease,"  as 
it  is  called.  If  a  piece  of  tin  in  process  of  change  from 
its  metallic  state  to  the  gray-powder  form  is  brought 
into  contact  with  ordinary  white  tin,  the  "disease" 
will  catch.  And  all  the  while  it  is  neither  more  nor 
less  than  tin.  These  forms  are  merely  its  allotropic 
modifications. 

It  is  found  in  Cornwall,  England,  in  the  Malay 
Archipelago,  in  Bolivia,  Australia,  Bohemia,  and 
Saxony.  The  usual  ore  is  tinstone  or  cassiterite,  and 
is  stannic  oxide,  Sn02,  combined  with  the  arsenical, 
copper,  and  other  mineral  sulphides  and  tungstates. 
There  is  also  a  comparatively  rare  tin  pyrites,  being 
sulphide  of  tin,  copper,  iron,  and  sometimes  zinc. 
The  ore  is  smelted,  and  the  resultant  metal  is  about 
ggJ/2  per  cent.  pure. 

It  dissolves  in  hydrochloric  acid  to  stannous 
chloride 

Sn  +  2HC1  =  SnCl2  +  H2. 

Cold  sulphuric  acid  attacks  it  but  slightly,  while  con- 
centrated hot  sulphuric  acid  not  only  dissolves  it, 
forming  stannous  sulphate,  but  it  liberates  sulphur 
dioxide : 


Sn 

+    2H2SO4 

=     SnSO4     - 

f     S02     + 

2H2O. 

tin 

sulphuric 

stannous 

sulphur 

water 

acid 

sulphate 

dioxide 

185 

EVERYMAN'S    CHEMISTRY 

It  would  appear  to  make  the  sulphuric  acid  a  little 
nervous  by  the  way  it  liberates  sulphur  dioxide. 

Pure  nitric  acid  is  practically  without  action  on  the 
metal.  With  dilute,  cold  nitric  acid  stannous  nitrate 
is  formed;  but  if  brought  together  with  somewhat 
stronger  nitric  acid,  it  oxidizes  to  metastannic  acid 
— which  we  shall  consider  shortly.  Observe,  please, 
we  have  been  getting  stannous  compounds  with 
Sn11,  or  with  two  hooks,  rather  than  the.  stannic  with 
SnIV,  or  four  hooks. 

Now,  although  tin  remains  untarnished  on  exposure 
to  the  air,  its  salts,  as,  for  instance,  a  solution  of 
stannous  chloride  (SnCl2),  will  absorb  oxygen  and 
stannic  hydroxide  (Sn(OH)4)  is  formed;  and  if  we 
bring  ammonia  into  this  solution,  there  is  precipitated 
out  stannic  acid,  H2SnO3.  This  loses  water  and  goes 
back  to  the  anhydrid,  stannic  oxide,  SnO2.  Then  if 
we  fuse  this  with  caustic  soda  we  have: 

SnO2     +    2NaOH     =     Na2SnO3     +     H2O. 
stannic  caustic  sodium  water 

oxide  soda  stannate 

There  is  another  stannic  acid,  but  we  shall  not 
consider  it.  What  I  ask  you  to  do  is  to  look  back 
and  see  how  this  metal  forms  salts  with  acids,  prin- 
cipally as  a  base  with  two  equivalents  for  combining, 
and  then,  after  a  little  legerdemain  with  its  chloride, 
comes  out  in  the  stannic  form  with  four  hooks,  oxidizes, 
and  proceeds  to  do  business  as  an  acid. 

Of  course,  truth  is  relative,  and  so  are  acids  and 
bases.  Ammonia  is  not  a  very  strong  base,  and  there- 
fore there  is  no  stannate  of  ammonium.  On  the 
other  hand,  sodium  is  much  more  alkaline  than  tin, 
and  so  we  have  the  stannate  of  sodium.  Why  weak 
nitric  acid  should  make  a  nitrate  of  tin  (stannous 

;86 


MORE   METALS 

nitrate)  and  strong  nitric  acid  should  oxidize,  is  one 
of  those  things  that  are  easier  to  remember  than  ex- 
plain. We  know,  however,  that  nitric  acid  is  a  great 
oxidizing  agent. 

Stannous  chloride,  SnCl2,  is  a  white  salt  used  in  the 
textile  industry  and  especially  in  dyeing.  It  is  also 
used  for  weighting  silks,  and  here  again  we  have 
trouble.  Fire  insurance  men  know  that  silks  heavily 
weighted  with  chloride  of  tin  are  liable,  under  cer- 
tain conditions,  to  spontaneous  combustion.  We  get 
an  intimation  of  this  in  the  action  of  the  chloride 
above  referred  to,  which  absorbed  oxygen,  produc- 
ing stannic  hydroxide  and  then  stannic  acid.  The 
fire  starts  in  that  disposition  to  oxidize. 

Stannic  chloride,  SnCl4,  is  formed  by  the  action  of 
chlorine  upon  stannous  chloride  SnCl2,  and  is  a 
fuming  liquid. 

There  are  two  sulphides:  SnS  and  SnSz,  the  stan- 
nous compound  being  a  brown,  smeary  mess,  while 
the  stannic  sulphide  is  a  yellow,  crystalline  body  used 
as  " mosaic  gold"  and  " bronze  powder." 

The  world's  output  of  metallic  tin  amounted  to 
120,400  tons  in  1914.  This  is,  of  course,  mainly  con- 
sumed in  the  manufacture  of  tin-plate,  an  important 
industry  in  this  country  and  in  Wales.  At  the  present 
time  tin  ore,  cassiterite  from  Bolivia,  is  being  smelted 
in  the  United  States ;  the  Straits  Settlements,  however, 
are  the  world's  principal  source. 

LEAD. — When  you  come  right  down  to  it,  some 
metals  are  no  better  than  nitrogen  in  the  way  of  being 
plain-spoken  and  easily  understood.  Lead  is  more 
dependable  than  tin  in  its  chemical  reactions,  and 
yet  it  is  full  of  tricks.  Its  valency — that  is,  its  num- 
ber of  bonds  for  combining — is  like  that  of  tin :  some- 

187 


EVERYMAN'S   CHEMISTRY 

times  there  are  two  and  sometimes  four.  Having 
settled  upon  this,  we  shall  shortly  have  to  consider 
lead  suboxide,  Pb2O,  and  unless  we  want  to  guess 
that  the  molecule  is  a  kind  of  triangle  with  two  lead 
atoms  hooked  together  in  a  way  that  they  show  no 
disposition  to  unite  — 


Lead  5ubo//de 

we  had  better  pass  over  the  matter  on  the  ground 
that  this  is  not  the  proper  place  to  discuss  it. 

Lead  is  found  usually  as  the  sulphide  in  a  mineral 
called  galena  or  galenite,  so  we  might  well  say  that 
the  inner  significance  of  Galena,  Illinois,  is  sulphide 
of  lead.  The  ores  are  roasted  and  smelted  some- 
what as  tin  and  zinc,  and  yet  with  enough  differences 
to  make  them  subjects  of  separate  and  special  studies. 

Lead  is  a  blue-gray  metal  with  a  bright  luster  when 
freshly  cut,  which  quickly  grows  dull  on  exposure  to 
the  air.  This  is  probably  due  to  a  thin  film  of  an  oxide 
which  in  time  becomes  a  carbonate.  Perfectly  dry 
air  and  water  that  is  free  from  dissolved  air  leave 
it  bright  —  have  no  action  upon  it.  It  is  not  tough 
enough  to  be  drawn  into  wire  or  hammered  into  thin 
foil,  but  it  may  be  rolled  into  sheets  of  foil  and  pressed 
into  pipes.  If  lead  filings  are  compressed  under  a 
pressure  of  thirteen  tons  per  square  inch,  they  will  form 
into  a  solid  block  as  though  they  had  been  melted; 
and  if  a  pressure  of  thirty-three  tons  per  square  inch 
is  brought  upon  the  metal,  it  seems  to  liquefy. 

If  lead  is  brought  into  contact  with  water  which 
holds  carbon  dioxide  in  solution  and  is  nearly  free 
from  other  bodies,  as,  for  instance,  rain-water,  a  solu- 
ble carbonate  of  lead  may  be  formed.  This  is  dan- 

188 


MORE    METALS 

gerous,  and  if  the  water-supply  of  a  town  is  pure 
and  free  from  hardness  it  is  sometimes  necessary  to 
filter  it  through  limestone  or  chalk  to  give  it  sufficient 
hardness  to  avoid  the  formation  of  the  poison  from 
lead  pipes.  Hard  water  forms  a  coating  of  insoluble 
salts  which  cover  it  and  avoid  the  danger  of  poisoning. 
All  lead  salts  are  poisonous. 

Lead  poisoning  is  a  mean  affliction,  and  is  cumu- 
lative— that  is,  we  never  get  used  to  it — and  as  we 
are  more  and  more  subjected  to  it  the  worse  it  grows. 
If  rain-water  is  used  for  drinking,  it  is  better  not  to 
have  the  gutters  and  leaders  made  of  lead ;  and,  owing 
to  the  solvent  action  of  organic  acids  upon  it,  if  cook- 
ing-vessels are  plated  with  tin  containing  lead,  they 
may  contaminate  the  food  with  poisonous  lead  com- 
pounds. 

There  are  chlorides  and  iodides  of  lead,  but  they 
are  not  very  important,  whereas  its  oxygen  com- 
pounds are  five  in  number  and  are  widely  used. 

Lead  suboxide,  Pb2O,  is  supposed  to  be  the  thin 
coating  formed  on  lead  when  exposed  to  the  air. 
It  may  be  produced  by  heating  certain  organic  salts 
of  the  metal,  and  is  a  dark-gray  powder. 

Lead  monoxide,  or  litharge,  PbO,  is  a  reddish 
yellow  crystalline  body,  sold  as  a  yellow  pigment.  It 
is  also  used  in  glass-making. 

Lead  sesquioxide,  Pb203,  is  an  orange-yellow  pow- 
der that  is  not  very  stable,  going  over  into  the  mon- 
oxide and  dioxide. 

Lead  tetroxide,  Pb304,  red  lead  or  minium,  is  formed 
by  heating  lead  monoxide  or  white  lead  in  the  air  to 
35o°-5oo°.  It  is  a  scarlet  powder  which,  on  heating, 
grows  deeper  in  tint,  then  violet,  and  finally  black, 
becoming  red  as  it  is  cooled  off.  It  is  the  very  oppo- 
site of  almost  everything  else  in  that,  instead  of  grow- 

189 


EVERYMAN'S    CHEMISTRY 

ing  red-hot,  it  becomes  black-hot  and  red-cold.  Hy- 
drogen sulphide  in  the  air  will  also  turn  it  black.  It 
is  not  as  stable  a  red  as  vermilion  (mercuric  sulphide) 
because  of  this  quality,  but  it  is  an  excellent  paint 
for  iron.  The  reason  why  it  is  better  as  well  as 
cheaper  for  ironwork  is  because  the  iron  displaces  the 
sulphur  in  mercuric  sulphide,  but  it  is  unable  to  lure 
the  sulphur  away  from  its  combination  with  lead 
in  this  form. 

Lead  dioxide,  sometimes  called  lead  peroxide,  PbO2, 
is  a  brown  powder  and  is  an  oxidizing  agent.  For  this 
reason  it  is  not  very  stable.  If  a  stream  of  hydrogen 
sulphide  is  brought  into  contact  with  it,  the  gas  will 
catch  fire. 

About  513,000  tons  of  lead  were  produced  in  the 
United  States  in  1914.  The  lead  ores  of  the  Missis- 
sippi Valley  and  a  little  of  the  ore  received  from  certain 
of  the  Western  States  are  almost  free  from  silver, 
and  the  metal  produced  from  them  is  known  as  ' '  soft 
lead."  Over  200,000  tons  of  soft  lead  were  produced 
in  1914. 

The  greatest  uses  of  the  metal  are  for  protection 
against  sulphuric  acid,  as  in  acid-chambers  and  lead- 
lined  tanks,  and  for  plumbers'  piping  and  supplies. 

The  Storage  Battery. — Improvements  in  storage  bat- 
teries provide  for  the  use  of  other  metals  than  lead, 
but  lead  is  the  old  standard,  and  with  it  the  principle 
may  be  explained.  If  two  corrugated  lead  plates  are 
covered  with  a  paste  of  litharge,  PbO,  and  dipped 
into  a  20  per  cent,  solution  of  sulphuric  acid,  the 
litharge  on  the  plates  is  converted  into  the  sulphate 
PbSCV  Now  if  you  pass  an  electric  current  through 
the  cell,  hydrogen  is  evolved  at  one  pole  and  oxygen 
at  the  other.  You  may  remember  that  by  a  current 

190 


MORE    METALS 

of  electricity  through  water  containing  an  electrolyte 
like  sulphuric  acid  the  water  is  decomposed  into  its 
elemental  parts,  the  hydrogen  going  to  one  pole  and 
the  oxygen  to  the  other.  Then,  having  the  thin  coat- 
ing of  lead  sulphate  on  each  pole,  let  us  see  what 
happens:  the  hydrogen  takes  the  place  of  the  lead 
in  the  sulphate,  producing  a  gray  film  of  spongy 
metallic  lead  and  sulphuric  acid.  Here  is  the  reaction : 

PbSO4     +     H2     =     H2SO4     -h    Pb. 
sulphate       hydro-      sulphuric        lead 
of  lead  gen  acid 

At  the  anode,  or  other  pole,  the  oxygen  goes  to 
work  also ;  it  transforms  the  lead  sulphate,  PbSO4,  into 
lead  persulphate,  Pb(SO4)2,  with  the  help  of  the  sul- 
phuric acid  present : 

2PbSO4     +     2H2SO4     +     O2     =     2Pb(SO4)2.    +     2H2O. 
lead  sulphuric         oxy-  lead  per-  water 

sulphate  acid  gen  sulphate 

This  persulphate  is  acted  on  by  the  water,  is  hydrol- 
ized  into  sulphuric  acid  and  lead  peroxide — here  we 
have  it : 

Pb(SO4)2     +    2H2O     =     PbO2     +    2H2SO4 
lead  per-  water         lead  per-       sulphuric 

sulphate  oxide  acid 

— and  a  dark-brown  film  of  the  lead  dioxide  (or  per- 
oxide) is  formed  on  the  lead  plate.  Thus  we  have 
spongy  metallic  lead  on  one  pole  and  brown  lead 
peroxide  on  the  other,  and  we  can  shut  off  the  current. 
The  battery  is  "charged." 

Now  let  us  hark  back  to  the  ionic  theory,  which  we 
considered  in  the  early  part  of  the  book,  and  remem- 
ber that  sulphuric  acid  is  an  electrolyte  and  that 

191 


EVERYMAN'S    CHEMISTRY 

it  splits  up  into  ions  with  positive  and  negative 
charges.  These  ions,  hydrogen  and  S04,  are  skim- 
ming about,  ready  for  business.  The  hydrogen  ions 
travel  over  to  the  plate  with  the  brown  PbO2  powder, 
and  they  reduce  the  lead  peroxide  to  lead  monoxide, 
or  litharge,  again. 

Observe:  2H+PbO2=H2O+PbO,  which  brings 
us  back  just  where  we  started,  except  for  the  fact 
that  the  hydrogen  ions  gave  up  their  positive  charge 
as  soon  as  they  struck  this  pole,  and  for  every  mole- 
cule of  PbO2  reduced  to  PbO  there  are  two  positive 
charges  of  electricity  delivered  at  that  pole.  On  the 
other  hand,  the  SO4  ions  travel  over  to  the  other  pole 
and  convert  the  spongy  lead  to  the  sulphate,  thus : 

S04    +    Pb    =    PbS04, 

sul-  lead  lead 

phanion  sulphate 

and  the  S04  ions,  giving  up  their  negative  charges 
upon  the  plate,  you  have  one  pole  with  a  positive 
charge  and  the  other  with  a  negative  charge.  Now, 
as  the  two  leaden  plates  which  serve  as  poles  are  con- 
nected by  wire,  if  you  measure  the  current  you  find 
it  to  be  about  two  volts,  and  this  will  continue  for 
about  twelve  hours.  The  current  continues  as  long 
as  there  is  any  of  the  brown  lead  peroxide  left  on  one 
of  the  plates.  When  this  is  gone  the  battery  is  said 
to  be  discharged. 

The  situation  is  then  the  same  as  before.  The  lead 
oxide,  or  litharge,  left  by  the  hydrogen  is  converted 
into  sulphate  of  lead  by  the  sulphuric  acid,  and  we 
have  once  more  the  sulphate  on  both  poles.  Then  the 
battery  is  "charged"  again  by  the  introduction  of 
an  electric  current.  In  other  words,  it  is  fully  charged 
when  lead  peroxide  covers  one  pole  and  spongy  lead 

192 


MORE    METALS 

the  other.  It  is  discharged  when  sulphate  of  lead 
covers  both  poles. 

There  are  hydroxides  of  lead  which  may  be  re- 
garded as  combinations  of  the  monoxide  (litharge) 
with  water,  and  which  with  acids  produce  lead  salts. 
But  with  the  more  alkaline  metals  sodium  and  potas- 
sium, they  act  as  an  acid  toward  them,  and  then 
we  have  lead  behaving  like  tin  and  producing  plumbic 
acid  and  forming  the  plumbates  of  Na  and  K. 

There  is  a  whole  range  of  lead  salts  in  which  lead 
is  the  base.  The  nitrate  is  soluble,  the  carbonate  is 
not,  whereas  the  bicarbonate  is  and  the  acetate  is  very 
soluble.  Because  of  its  sweetish  taste  the  acetate 
is  called  sugar  of  lead.  This  is  a  misleading  name, 
for  it  is  not  a  sugar  in  any  sense,  as  we  shall  observe 
in  organic  chemistry.  Like  all  lead  salts,  it  is  a  rank 
poison.  The  sulphate  is  insoluble,  as  is  also  the 
sulphide,  which,  as  galena,  is  a  crystalline  black  rock, 
but  which,  precipitated  out  of  a  solution,  is  a  black, 
smeary  mass.  This  is  the  stuff  that  develops  in  oil 
paints  when  the  artist  has  not  known  better  than  to 
mix  vermilion  (mercuric  sulphide)  with  white  lead, 
and  the  lead  drives  out  the  mercury,  taking  its  place 
as  lead  sulphide. 

White  lead  is  not  the  insoluble  carbonate,  but  rather 
a  basic  carbonate  or  a  mixture  of  lead  hydroxide  and 
carbonate.  The  following  formula  would  about  rep- 
resent it:  Pb(OH)2.2PbCO3.  There  are  many  dif- 
ferent ways  of  making  it.  The  oldest  is  called  the 
Dutch  process,  in  which  lead  disks,  or  "buckles,"  are 
placed  in  earthen  pots  that  contain  a  little  dilute 
acetic  acid.  These  are  piled  up  in  tiers  embedded  in 
tan-bark  or  manure  in  such  a  way  that  the  air  flows 
over  them.  The  tan-bark  or  the  manure  ferments  and 
produces  carbonic  acid,  which  in  turn  forms  the 


EVERYMAN'S    CHEMISTRY 

carbonate  of  lead  in  the  presence  of  the  acetic  acid 
which  seems  to  act  as  a  catalyst.  The  process  takes 
ninety  days,  whereas  other  processes  are  very  much 
shorter.  It  seems  absurd  to  spend  so  much  time 
over  a  problem  that  should  be  simple,  and  those 
who  make  white  lead  by  a  shorter  process  say  their 
product  is  just  as  good.  The  Dutch-process  people, 
on  the  other  hand,  declare  that  it  is  not,  and  that  the 
proof  of  their  contention  is  their  much  larger  sales. 
We  can  very  well  afford  to  let  them  fight  it  out.  If  the 
Dutch-process  product  really  is  better,  it  may  be 
shortened  some  day  with  the  help  of  colloidal  chem- 
istry. 


XVI 

STILL   MORE   METALS 

The  Grand  Old  Tramp  Who  Left  His  Mark— Cobalt— Nickel- 
Chromium — The  Goldschmidt  Process — Thermit — Chromium  in 
Combination — Tanning — A  Lopsided  Leather  Test  with  Police- 
men and  Letter-carriers — Manganese — Molybdenum — Tungsten 
— Uranium 

ONE  of  the  fathers  of  chemistry  was  old  Philippus 
Aureolus  Paracelsus  Bombastus  von  Hohenheim, 
known  as  Paracelsus.  He  was  born  in  Switzerland, 
in  1493,  and  died  in  Salzburg,  in  the  Austrian  Tyrol,  in 
1541.  "He  lived,"  says  one  writer  of  him,  "like  a 
pig,  looked  like  a  drover,  found  his  greatest  enjoy- 
ment in  the  company  of  the  most  dissolute  and  lowest 
rabble,  and  throughout  his  glorious  life  he  was  gen- 
erally drunk."  Another  writer  says :  "It  is  true  that 
his  life  offered  a  strong  contrast  to  his  mentality,  but 
he  was  a  man  of  noble  character  and  intentions,  a 
Christian  humanist  and  ambulatory  theosophist,  who 
hoped  to  inspire  mankind  with  a  love  of  conscientious- 
ness and  veracity,  and  to  restore  the  suffering  to 
health."  Take  your  choice.  I  wish  we  had  space 
to  devote  a  whole  chapter  to  the  old  boy  who  was 
active  as  a  teacher,  chemist,  physician,  writer  (over  a 
hundred  books  are  attributed  to  him),  and  as  a  tramp. 
In  working  over  copper  and  other  metals  he  was 
very  much  annoyed  by  two  bodies  that  he  could  not 
succeed  in  separating  and  yet  that  were  neither  cop- 

195 


EVERYMAN'S    CHEMISTRY 

per  nor  iron.  Sometimes  they  were  present  and  again 
they  were  not,  and  they  behaved  in  a  way  that  was 
no  less  than  devilish.  Now  in  the  Harz  Mountains 
they  have  been  familiar  with  evil  spirits  for  many 
centuries,  and  among  the  several  varieties  that  enjoy 
the  pursuit  of  happiness,  both  there  and  elsewhere, 
is  a  species  called  kobolds — which  at  times  I  confess 
I  am  disposed  to  believe  in  myself.  They  are  said  to 
be  less  than  three  inches  high,  usually,  and  they  can 
get  in  and  out  of  any  place.  It  is  their  especial 
pleasure  to  roll  your  collar-button  under  the  bed,  to 
move  your  chair  around  so  that  you  may  stub  your 
toe  against  it  if  you  get  up  during  the  night,  to  work 
your  penknife,  keys,  watch,  and  other  valuables  into 
upholstered  recesses  of  your  sofa  or  easy-chair,  and, 
generally,  to  hide  things.  Another  species  of  devils, 
less  clearly  defined,  were  known  as  little  Nicks  or 
Nickel.  So  old  Bombastus  referred  to  these  two  metals 
by  the  names  that  we  know  as  cobalt  and  nickel  to 
this  day. 

They  are  not  very  rare,  and  may  be  separated 
without  much  difficulty  by  electrolytic  processes  by 
those  that  know  how.  Both  are  silvery  white,  cobalt 
having  a  pinkish  tinge  and  nickel  a  faint  yellowish 
hue.  Or,  lest  your  eye  betray  you,  let  us  give  the 
definition  of  another  writer  and  say  that  cobalt  is 
slightly  bluer  than  nickel.  The  latter  definition  is 
more  evident  to  me.  Cobalt  is  less  tough  than  iron 
and  no  great  commercial  use  has  thus  far  been  found 
for  it  as  a  metal.  It  makes  two  series  of  compounds, 
with  two  bonds  and  with  three.  Cobaltous  chloride 
(CoCl2)  crystallizes  in  light-red  crystals  (CoCl2.6H2O) 
that  form  a  nearly  colorless  solution,  but  when  dehy- 
drated become  deep  blue.  By  this  means  an  invisible 
ink  is  made  which  does  not  show  until  the  paper  is 

196 


STILL    MORE    METALS 

heated,  and  thus  the  water  driven  off.  Then  it  be- 
comes blue.  Left  to  itself  it  gradually  takes  on  water 
from  the  air  and  becomes  invisible  again.  A  sort  of 
cobalt  glass  is  made  by  fusing  sand,  cobalt  oxide, 
and  potassium  nitrate,  which,  when  powdered,  be- 
comes a  blue  pigment  called  "smalt,"  and  is  used  in 
china-painting  and  by  artists.  Thenard's  blue  is  made 
by  calcining  cobalt  oxide  with  alumina. 

Nickel,  on  the  contrary,  is  very  widely  used.  It  is 
produced  in  great  quantity  at  Sudbury,  Ontario,  and 
is  found  along  with  copper  and  iron.  A  mixture  of  the 
three  metals  is  called  Monel  Metal  and  has  great 
strength  and  endurance.  It  is  used  for  propellers  of 
steamships  and  a  number  of  other  purposes.  Nickel 
alloyed  with  steel,  which  makes  it  very  hard  and 
tough,  is  used  as  nickel-steel  for  parts  of  machinery 
designed  to  withstand  continuous  wear  and  shocks, 
and  in  the  manufacture  of  armor,  burglar-proof  safes, 
etc.  As  nickel  does  not  tarnish  readily  in  the  air  and 
is  as  easy  to  apply  as  silver,  it  is  largely  used  in  elec- 
troplating. Nickel  coins  are  three  parts  copper  to  one 
of  nickel. 

Chromium  is  another  steel-gray  metal  which  does 
not  occur  free  in  nature,  but  usually  as  an  ore  called 
chromite,  which  is  a  chromite  of  iron  Fe(Cr02)2,  or  as 
an  oxide  mixed  with  earth  and  known  as  chrome  ocher. 
Traces  of  it  occur  in  emerald,  jade,  serpentine,  etc. 
The  usual  method  of  preparing  the  metal  is  by  the 
Goldschmidt  process,  whereby  the  inventor,  Prof. 
Hans  Goldschmidt,  produces  at  his  works  at  Essen 
about  100  kilos  (220  pounds)  at  a  charge.  He  mixes 
carefully  powdered  metallic  aluminium  and  chromium 
oxide  and  fills  a  refractory  clay  crucible  two- thirds  full 
with  it.  A  mixture  of  boron  peroxide,  which  gives  off 
oxygen  very  easily,  and  more  aluminium  or  magnesium 

197 


EVERYMAN'S    CHEMISTRY 

powder  is  placed  in  a  little  heap  over  the  center  of  the 
crucible  and  the  whole  covered  with  a  protective  layer 
of  feldspar.  A  piece  of  magnesium  ribbon  is  stuck  into 
the  pile  of  boron  peroxide  and  aluminium  or  mag- 
nesium powder,  and  when  the  crucible  has  been  prop- 
erly placed  on  a  sand-bath,  and  the  operator  has  pro- 
vided himself  a  good  runway  to  avoid  accidents,  the 
magnesium  ribbon  is  ignited.  In  the  reaction  which 
follows  a  temperature  of  3,000°  centigrade  is  reached: 

Cr208     +    2A1     =     2Cr    +    A12O3. 

chromium        alu-  chro-        alumina 

sesqui-        minium  mium 
oxide  v 

When  the  crucible  is  cold  the  chromium  is  found  at 
the  bottom,  while  the  slag  is  fused  alumina,  a  kind  of 
artificial  corundum.  A  number  of  other  metals,  in- 
cluding manganese,  vanadium  and  tantalum,  may  be 
produced  in  the  same  manner,  as  we  shall  see. 

The  reaction  is  also  the  principle  of  Goldschmidt's 
thermit,  which  is  used  for  welding  shafts,  rails,  and 
broken  pieces  of  heavy  machinery.  The  crucible  for 
this  purpose  is  cone-shaped,  and  the  charge  is  iron 
oxide  with  aluminium  powder,  because  molten  iron  is 
what  is  wanted.  The  reaction  then  is : 

Fe203     +     2A1     =     2Fe     +     A12O3 
ferric  alu-  iron          alumina 

oxide         minium 

The  ends  of  the  broken  shaft  or  part  are  heated  and 
brought  together  and  a  mold  built  around  the  place 
to  be  welded.  Then  the  thermit  cone  is  placed  above 
the  opening  in  the  mold,  little  end  down,  and  the 
reaction  is  started.  The  molten  iron  runs  right  in 
where  it  is  needed,  through  an  opening  at  the  point 
of  the  cone,  making  a  complete  joint. 

198 


STILL    MORE    METALS 

In  the  steel  industry  the  metal  is  usually  intro- 
duced in  the  form  of  ferro-chromium,  which  is  made 
by  smelting  chromite  in  an  electric  furnace.  It  con- 
tains over  60  per  cent,  of  chromium  and  less  than 
2  per  cent,  of  carbon.  Steel  with  i^  or  2  per  cent, 
of  carbon  and  2^  to  4  per  cent,  of  chromium  is  drill- 
proof;  it  cannot  be  worked  with  ordinary  hardened 
tool-steel.  Chrome-nickel  steel  is  used  for  armor-plate. 

Chromium  combines  with  oxygen  and  hydrogen  to 
a  series  of  oxides  and  hydroxides  that  are  mild  acids 
and  bases,  very  much  according  to  the  company  they 
are  in.  They  are  employed  in  making  paints,  of  which 
the  best  known  is  the  oxide  to  which  we  have  referred, 
and  known  as  yellow  ocher.  When  this  has  been 
heated  it  becomes  a  red  orange  and  is  called  burnt 
sienna.  The  well-known  intense  chrome  yellow  is  a 
chromate  of  lead,  PbCrO4.  Chrome  green  is  the 
sesquioxide,  Cr2O3. 

Bichromate  of  potash,  K2Cr2O7,  is  a  great  oxidizing 
agent,  going  over  on  slight  provocation  to  Cr2Os  and 
letting  loose  a  lot  of  oxygen.  This  is  used  in  bleach- 
ing, dyeing,  calico-printing,  and  in  chemical  industry. 
It  is  employed  in  photography,  because  gelatin,  mixed 
with  it,  becomes  hard  and  insoluble  in  the  light.  If  a 
pigment  is  mixed  with  gelatin  and  dichromate  of  pot- 
ash in  the  dark,  and,  still  in  the  dark,  applied  to  paper 
and  put  under  a  photographic  negative  and  then  ex- 
posed to  the  light,  the  gelatin  which  holds  the  pig- 
ment in  suspension  will  glue  itself  on,  hard  and  insol- 
uble, to  the  paper  wherever  the  light  has  struck  it. 
Then  if,  back  in  the  dark-room,  the  paper  is  removed 
and  washed,  everything  will  wash  off  except  where 
the  light  has  struck  through  the  negative.  That  is 
the  way  the  beautiful  carbon  prints  are  made. 

This  effect  of  dichromate  of  potash  on  gelatin  gives 
14  199 


EVERYMAN'S    CHEMISTRY 

a  hint  of  the  reason  for  chrome  tanning.  Tanning  is 
still  more  of  an  art  than  a  science,  as  witness  the  use 
of  dog  dung  for  making  morocco  and  horse  grease  for 
crown  leather.  There  is  no  reason  why  such  materials 
should  not  be  employed,  but  they  are  likely  to  indi- 
cate that  the  chemical  reactions  are  not  yet  thor- 
oughly known.  The  skins  of  animals  consist  in  gen- 
eral of  two  layers,  of  which  the  outside,  or  epidermis, 
is  made  up  of  simple,  hardened,  and  flattened  cells, 
while  underneath  these  the  cells  are  soft  and  spherical 
and  are  referred  to  as  the  mucous  layer.  The  harden- 
ing of  the  gelatinous  mass  and  rendering  it  so  that 
it  will  not  putrefy  is  the  main  business  of  tanning. 
I  take  it  that  by  this  time  you  will  have  observed 
that  the  chemistry  of  tanning  is  a  very  complex  sub- 
ject and  that  many  of  its  problems  have  not  yet  been 
mastered.  We  shall  not  even  take  it  up  in  organic 
chemistry.  The  tannins,  which  we  shall  merely  note 
in  passing  later,  are  found  in  many  woods  and  barks 
and  reach  the  tanner  either  as  wood  or  bark  or  in 
the  form  of  extracts.  But  the  shorter  process  of  min- 
eral tanning  has  come  into  frequent  use,  and  here  the 
chromium  salts  lead.  It  has  become  a  great  industry, 
especially  in  the  preparation  of  upper  leathers.  There 
is  a  method  of  combined  chrome  and  extract  tanning 
that  produces  sole-leather  of  remarkable  endurance. 
A  considerable  number  of  policemen  and  letter- 
carriers  were  shod  with  one  boot  soled  with  the  best 
oak-tanned  sole-leather  available,  and  the  other  with 
that  made  by  the  new  process.  The  new-process 
leather  outlasted  the  old  in  the  ratio  of  nearly  three 
to  one.  Why  the  new  method  has  not  come  into  use 
would  be  a  mystery  if  it  were  not  for  the  fact  that 
inventions  that  offer  no  immediate  profits  to  industry 
are  often  hard  to  get  started.  When  the  general 

200 


STILL   MORE    METALS 

public  is  better  informed  about  chemical  processes  we 
shall  not  have  to  wait  so  long  for  improvements. 

Now  let  us  note  a  few  more  metals  that  are 
frequently  heard  of  in  connection  with  the  steel  in- 
dustry. Some  have  other  uses  also. 

Manganese  is  a  gray  metal  with  a  reddish  tinge  that 
rusts  in  moist  air  like  iron,  and  is  occasionally  found 
with  that  metal  in  the  form  of  one  of  its  many  oxides. 
It  is  brittle  and  harder  than  iron,  and  is  most  easily 
prepared,  like  chromium,  by  the  Goldschmidt  process. 
It  is  frequently  brought  upon  the  market  in  the  form 
of  ferro-manganese,  which  contains  it  in  varying  pro- 
portions. Ferro-manganese  is  needed  to  reduce  the 
iron  oxides  in  Bessemer-steel  converters,  in  which  the 
manganese  picks  up  the  oxygen  from  the  iron  and 
goes  off  with  it  into  the  slag.  Alloyed  with  steel, 
manganese  makes  it  very  hard  and  free  from  air- 
holes. This  is  frequently  used  for  burglar-proof  safes, 
dredge-pins,  crusher-plates  for  ore-mills,  and  the  like. 
Manganese  is  also  alloyed  with  other  metals,  chiefly 
for  its  hardening  effect. 

Chemically  it  is  interesting — ana  perplexing.  In 
the  matter  of  valence  it  sometimes  has  two,  some- 
times three,  and  at  others  four,  six,  or  even  seven 
bonds,  or  hooks,  for  combining.  It  forms  a  whole 
series  of  oxides,  of  which  the  lower  ones  are  basic  and 
the  higher  ones  acid  in  their  reactions.  Permanganic 
acid  makes  salts  with  the  alkalies  that  are  great 
oxidizing  agents,  the  permanganate  of  potash  being 
often  used  in  the  laboratory  and  in  medicine.  Its 
crystals  are  purple  with  a  greenish  luster,  but  in  solu- 
tion it  is  deep  red.  When  the  higher  oxides  of  man- 
ganese are  heated  they  give  off  oxygen  and  revert  to 
a  lower  type.  We  have  already  noted  the  use  of  man- 
ganese compounds  in  glass-making. 

201 


EVERYMAN'S    CHEMISTRY 

Molybdenum  is  found  usually  as  a  sulphide,  MoS2, 
known  as  molybdenite,  and  as  wulfenite,  a  molybdate 
of  lead,  PbMoO4,  but  chiefly  as  the  sulphide.  The 
pure  metal  is  softer  than  steel  and  yields  readily  to 
forging  and  welding.  But  when  it  is  added  to  molten 
steel  in  very  small  quantities,  it  is  reported  that 
molybdenum  nearly  doubles  its  tensile  strength,  adds 
to  its  capacity  for  elongation,  to  its  toughness,  its 
fineness  of  grain,  and  retention  of  magnetism.  It  has 
been  used  by  the  Germans  for  lining  their  enormous 
howitzers,  while  projectiles  of  molybdenum  steel  are 
found  to  have  great  power  of  penetration.  It  is  also 
desirable  for  strong  wire,  rifle-barrels,  propeller-shafts, 
and  wherever  great  strength  is  needed. 

Tungsten  is  very  like  molybdenum  in  its  compounds, 
and  it  has  an  effect  similar  to  that  of  molybdenum 
when  alloyed  with  steel.  It  is  found  in  the  mineral 
scheelite,  which  derives  its  properties  from  tungstate 
of  calcium,  CaWO4,  and  wolframite,  FeWO4.  The 
symbol  W  is  from  the  German  name  of  the  element, 
wolfram.  The  very  weak  tungstic  acid  combines 
with  strong  alkalies,  and  of  these  an  interesting  use 
has  been  found  for  the  tungstate  of  sodium,  Na2WO4. 
Cotton  cloth  soaked  in  a  solution  of  this  will  not  burn 
with  a  flame,  but  at  most  only  smolders  away  slowly. 
Lead  tungstate  is  a  good  white  paint,  while  tungsten 
trioxide  is  a  canary-yellow  pigment.  The  greatest  use 
for  the  metal  is  for  filaments  in  electric-light  bulbs. 

Uranium  is  found  in  pitchblende,  and,  like  manga- 
nese, molybdenum,  and  tungsten,  is  indefinite  in 
valency.  Sodium  diuranate,  Na2U2O7,  is  known  as 
uranium  yellow,  and  is  used  for  coloring  glass  and 
for  pottery  glazes.  Just  now  there  is  considerable  dis- 
cussion going  on  as  to  the  merits  of  alloys  of  steel 

with  uranium. 

202 


XVII 

SOME  OF  THE  RARER  METALS 

Silver — Its  Many  Different  Colors — Chemistry — Coinage — Electro- 
plating— How  to  Clean  Silver — Silver  Salts — Photography — The 
Great  Domain  of  the  Chemistry  of  Light — Gold — All  Gold  Does 
Not  Glitter — Metallurgy — Gold  when  It  Is  Red — Some  Figures 
About  It — Platinum  and  Its  Family — Mercury — Compounds — 
Radium 

SILVER  is  valuable  because  it  is  rare,  but  if  it 
were  not  so  rare  we  should  use  a  great  deal  more 
of  it.  It  is  a  better  conductor  of  heat  and  electricity 
than  copper,  and  it  is  "noble"  in  that  it  is  more  en- 
during than  iron,  copper,  or  other  metals — that  is, 
it  is  not  so  easily  oxidized.  It  occurs  in  a  free  state 
in  nature;  occasionally  it  is  found  in  large  masses, 
crystallized  in  cubes — which  fill  the  miner's  heart 
with  joy.  More  frequently,  however,  it  occurs  with 
copper  and  other  metals  as  the  sulphide,  Ag2S, 
called  argenite. 

Its  use  is  older  than  history.  The  Phoenicians  are 
supposed  to  have  derived  their  great  wealth  of  it  from 
Spain  and  Armenia.  It  is  a  white,  lustrous  metal, 
but  light  reflected  back  and  forth  from  its  surfaces 
many  times  is  yellow.  Very  thin  layers  of  it  have  a 
blue  tint.  The  vapors  of  it  are  green.  Powdered 
silver  is  gray  and  has  an  earthy  appearance.  It  is 
highly  malleable  and  ductile.  The  air  does  not  affect 
it  unless  it  has  hydrogen  sulphide,  H2S,  in  it;  then  it  is 

203 


EVERYMAN'S    CHEMISTRY 

blafckened,  owing  to  a  thin  layer  of  silver  sulphide, 
Ag2S,  in  which  the  silver  has  replaced  the  hydrogen. 

Dilute  sulphuric  acid  does  not  affect  it,  but  hot 
concentrated  sulphuric  acid  produces  silver  sulphate, 
Ag2SO4.  Hydrochloric  acid  acts  slowly  upon  it  until 
a  high  temperature  is  reached,  when  the  insoluble 
silver  chloride,  AgCl,  is  formed.  Nitric  acid,  on  the 
other  hand,  dissolves  it  readily,  hot  or  cold,  strong  or 
dilute,  forming  nitrate  of  silver,  AgNO3. 

The  susceptibility  of  silver  to  the  action  of  sulphur 
is  so  great  that  even  that  which  is  contained  in  the 
yolks  of  eggs  will  tarnish  a  silver  chafing-dish  if  left  in 
it  any  length  of  time.  The  sulphur  in  an  ordinary 
elastic  rubber  band  will  quickly  tarnish  a  pocketful  of 
silver  coins. 

Pure  silver  is  rather  soft  to  be  used  alone,  and  for 
coins  it  is  usually  alloyed  with  copper.  Sterling  silver, 
as  the  British  standard  of  coinage  is  called,  is  92  X 
per  cent,  silver  and  7^  per  cent,  copper.  The  coin- 
age of  the  United  States  is  90  per  cent,  silver  and  10 
per  cent,  copper.  Articles  of  standard  silver  may  be 
heated  so  as  to  oxidize  the  copper  near  the  surface, 
and  this  oxidized  copper  is  removed  by  immersing  the 
article  in  a  bath  of  dilute  sulphuric  acid,  which  re- 
moves the  copper  by  dissolving  it  and  forming  the 
soluble  copper  sulphate  CuSO4,  leaving  a  thin  film  of 
pure  silver  behind.  This  is  known  as  " frosted  silver." 
So-called  "oxidized  silver"  is  not  oxidized  at  all. 
Silver  ornaments  a're  dipped  in  a  solution  of  an  alka- 
line sulphide,  and  this  deposits  a  film  of  the  dark 
silver  sulphide  upon  the  metal,  the  silver  taking  up 
the  sulphur  according  to  its  wont. 

Silver  is  easily  taken  out  of  solution  and  precipitated 
upon  other  bodies  by  electricity,  and  silver  electro- 
plating is  an  important  industry.  Sheffield  plate,  how- 

204 


SOME  OF  THE  RARER  METALS 

ever,  is  not  silver  plated  upon  a  baser  metal,  but,  if 
genuine,  consists  of  copper  and  silver  sheets  that  have 
been  rolled  together  at  a  little  below  the  melting- 
point  of  silver. 

To  clean  silver,  the  best  way  is  to  do  so  electrically, 
and  this  may  be  done  conveniently  in  any  kitchen 
or  butler's  pantry.  The  first  requisite  is  an  earthen- 
ware pot.  Metal  will  not  do.  Then  put  into  the  pot 
one  or  two  pieces  of  zinc  or  aluminium,  such  as  may  be 
purchased  at  nearly  any  hardware-store.  One  or 
two  pieces  of  sheet-metal,  say  four  by  ten  inches, 
will  be  enough.  Fill  the  pot  one-half  to  two-thirds 
full  of  hot  water  and  add  two  or  three  heaping  table- 
spoonfuls  each  of  table  salt  and  of  bicarbonate  of  soda. 
These  are  the  electrolytes.  Then  put  in  the  tarnished 
silverware,  and  it  will  grow  bright  in  a  little  while. 

We  must  go  back  to  the  ionization  theory  to  explain 
this.  Both  zinc  and  aluminium  are  electropositive 
to  silver,  and  a  current  is  set  up  between  them.  The 
salt,  NaCl,  splits  into  sodium  and  chlorine  ions,  the 
chlorine  ions  going  over  to  the  zinc  and  forming  zinc 
chloride,  which  goes  into  solution.  The  sodium  ions  go 
to  the  other  pole,  which  are  the  silver  articles.  Here 
they  act  upon  water,  release  hydrogen,  and  form  caustic 
soda: 

Na2     +    2H20     =     2NaOH     +    H2 
sodium        water  caustic      hydro- 

soda          gen 

The  hydrogen  just  released  acts  upon  the  silver  sul- 
phide and  produces  hydrogen  sulphide  and  free  silver: 

Ag2S     +     H2     =     H2S     +     2Ag 
silver        hydro-    hydrogen      silver 
sulphate        gen        sulphide 

That  free  silver  is  now  just  where  it  is  desired — on 
the  outside  of  the  spoons,  or  wherever  it  was  before 

205 


EVERYMAN'S    CHEMISTRY 

it  was  tarnished.  All  grease  must  be  removed  before 
the  articles  are  put  into  the  pot. 

The  preparations  that  are  sold  that  plate  silver  on 
places  where  brass  or  base  metal  is  exposed  contain 
a  little  silver  in  a  condition  of  chemical  instability. 
When  it  meets  the  baser  metal  an  exchange  of  acid 
and  base  occurs,  the  silver  being  deposited  upon  the 
vessel  in  the  place  of  the  copper  taken  up  by  the 
former  silver  salt  solution. 

Cyanide  of  sodium  and  of  potassium  have  the 
faculty  of  making  a  soluble  silver  salt.  It  is  not  silver 
cyanide,  AgCN,  which  is  insoluble,  but  a  double  salt, 
the  sodium  (or  potassium)  silver  cyanide,  Na.Ag(CN)2. 
These  cyanides  are  so  wickedly  poisonous  that  it  is 
no  less  than  a  crime  to  sell  them  in  silver  polishes, 
although  they  dissolve  silver  in  almost  any  form, 
including  the  black  sulphide.  Thiosulphate  of  soda, 
which  the  photographic  people  call  "hypo,"  will  also 
make  a  complex  soluble  salt,  but  not  so  easily  as  the 
cyanides. 

Cyanide  of  soda  is  largely  used  in  the  extraction  of 
silver  from  its  ores. 

Chloride  of  silver  is  a  white,  cheese-like  mass,  in- 
soluble in  water,  and  is  formed  when  a  solution  of  a 
silver  salt  and  nearly  any  chloride  are  brought  to- 
gether. On  exposure  to  the  light  it  turns  dark — 
please  mark  this,  as  we  shall  come  back  to  it 
presently. 

Nitrate  of  silver  may  be  obtained  by  treating  the 
metal  with  nitric  acid.  It  produces  colorless  crystals 
which  melt  at  218°  centigrade.  It  is  cast  in  thin 
sticks  and  used  in  medicine  as  "lunar  caustic"  because 
it  combines  with  albumens  to  form  insoluble  com- 
pounds. It  gets  its  name  from  the  old  term  of  the 
alchemists,  who  referred  to  silver  as  luna,  the  moon, 

206 


SOME  OF  THE  RARER  METALS 

and  had  for  its  sign  the  crescent.  The  nitrate  is  very 
soluble  in  water. 

There  are  oxides  of  silver,  but  as  they  are  not 
formed  on  the  heating  and  exposure  of  the  metal  to 
the  air,  we  shall  not  discuss  them. 

Since  silver  salts  are  the  active  agents  in  making 
photographic  images,  let  us  consider  what  happens, 
in  a  general  way,  in  the  making  of  a  photograph. 
You  will  remember  that  silver  chloride  turns  dark  on 
exposure  to  the  light.  The  bromide  and  iodide  have 
the  same  properties,  and  the  bromide  has  been  found 
the  more  available.  It  appears  that  under  the  action 
of  light,  a  subchloride,  Ag2Cl,  or  a  subbromide,  Ag2Br, 
is  formed,  but  how  they  hook  up  this  way  in  the  mole- 
cule is  not  clear,  since  both  silver  and  the  halogens 
are  monovalent.  But  bromine  does  some  tricks  for  a 
self-respecting,  monovalent  element,  and  we  might  as 
well  admit  that  this  whole  subject  of  valency,  or  the 
number  of  combining  hooks  or  bonds  that  the  atom 
of  an  element  has,  is  full  of  perplexity.  Suffice  it  to 
say  that  silver  bromide,  which  is  light  yellow  when 
first  produced,  becomes  dark  on  exposure  to  the  light. 
The  dry  photographic  plate  is  coated  with  an  emulsion 
of  gelatin  (in  a  colloidal  state,  you  observe),  and  the 
emulsion  contains  silver  bromide  in  a  very  finely 
divided  condition.  In  the  case  of  moving-picture 
films,  thin  strips  of  transparent  celluloid  are  coated  in 
the  same  way.  Now,  as  the  light  strikes  these  plates 
or  films,  the  bromide  of  silver  is  reduced  in  part,  and, 
according  to  the  strength  of  the  light,  from  silver  bromide, 
AgBr,  to  silver  subbromide,  Ag2Br.  The  negatives 
still  have  a  milky  white  appearance.  They  are  now 
put  into  a  developing  bath,  and  the  purpose  of  this  is 
to  reduce  the  silver  subbromide  to  metallic  silver. 
The  developers  are  mild  reducing  agents — ferrous  sul- 

207 


EVERYMAN'S   CHEMISTRY 

phate,  pyrogallol,  or  organic  compounds  which  have 
trade  names  such  as  hydroquinon,  metol,  etc.  What 
they  accomplish  is  to  take  up  that  bromine  in  the 
Ag2Br,  but  not  that  in  the  AgBr,  of  which,  of  course,  a 
great  deal  is  left  on  the  plate.  Then,  without  letting 
the  light  reach  the  plate,  it  is  further  immersed  in  a 
bath  of  "hypo,"  which  is  a  solution  of  sodium  thio- 
sulphate,  Na2S2O3,  and  this  dissolves  out  all  the  un- 
affected silver  bromide,  AgBr. 

There  is  now  nothing  left  in  the  plate  but  films  of 
silver,  with  particles  so  close  together  as  to  appear 
black  where  the  light  has  been  strongest,  particles  at 
greater  intervals  apart  in  the  shadows,  and  nothing  at 
all  where  there  was  no  light  to  change  the  silver  bro- 
mide that  was  originally  put  on  and  later  taken  off 
in  the  hypo  (thiosulphate)  bath.  This  is  a  negative — 
dark  where  the  original  was  light  and  light  where  the 
original  was  dark.  After  it  has  been  dried  it  is  placed 
upon  paper  that  is  also  coated  with  a  somewhat 
similar  solution  of  gelatin  and  silver  bromide  and  sub- 
jected to  the  light.  This  shines  through  the  light  spots 
in  the  negative  and  makes  the  corresponding  places 
dark  on  the  paper.  And  that  is  the  photograph. 

Photochemistry  is  a  very  big  subject  and  goes  much 
further  than  taking  photographs.  It  has  to  do  with 
the  chemical  action  of  light  —  and  of  radiant  heat 
obtained  from  the  rays  of  the  sun — and  there  are 
whole  Americas  to  be  discovered  within  that  domain. 

Let  us  consider  what  plants  do  by  means  of  photo- 
chemistry and  take  a  hint  or  two  from  them.  There 
are  two  bodies  in  the  leaves  of  plants  called  chlorophyl 
and  protoplasm.  Never  mind  the  chemical  formulas 
for  them;  it  would  be  too  much  like  guessing  for  us. 
But  there  they  are.  They  have  the  power  of  taking 
up  carbon  dioxide,  C02, from  the  air  and  water  which  is 

208 


SOME   OF   THE    RARER    METALS 

brought  to  them  in  rain  and  dew,  and  converting  them 
into  sugar,  starch,  and  cellulose.  Starch,  which  is 
needed  to  feed  the  germ  in  the  seed  cell,  and  cellulose, 
of  which  all  its  cells  are  made,  are  in  effect  bunched  or 
polymerized  molecules  of  sugar.  A  plant  can  do  that, 
and  we  can't,  but  that  is  not  to  the  point  just  now. 
We  are  discussing  the  photochemical  activities  of  chlo- 
rophyl  and  protoplasm.  Let  us  write  out  what  hap- 
pens to  the  water  and  carbon  dioxide: 


6CO2     +     5H2O     =     CiHioO6     +     6O2     —     671,000 
carbon          water  sugar  oxygen         calories 

dioxide  of  heat 

If  there  is  a  loss  of  671,000  calories  in  this  reaction, 
where  did  the  plant  get  the  heat  to  supply  it  ?  If  the 
cost  of  the  reaction  is  671,000  calories,  you  must  sup- 
ply them  if  the  reaction  is  to  take  place.  It  gets  this 
heat  from  the  sun. 

Therefore  every  stick  of  wood  we  burn  is  energy 
stored  up  by  the  sun.  The  sun  furnished  the  heat  to 
cause  the  reactions.  In  other  words,  to  make  the 
wood  out  of  water  and  CO2  gas  it  took  a  great  deal  of 
heat.  Now,  to  turn  that  wood  back  to  water  and  gas, 
the  same  heat  is  given  out.  That  is  the  way  we  get 
our  sunlight  back  when  we  sit  around  the  fire.  But 
this  is  not  all.  Except  the  little  work  done  by  water- 
power  (and  the  water  was  lifted  by  the  sun),  all  the 
energy  of  men  and  animals  comes  from  this  stored 
energy  of  the  sun.  All  our  food  is  from  that  source. 
In  every  movement,  every  thought,  we  avail  ourselves 
of  energy  gathered  from  the  sun. 

Now  observe  the  significance  of  photochemistry. 
We  have  touched  one  little  edge  of  it  in  making  pict- 
ures. We  find  that  ultra-violet  rays  of  light  destroy 
bacteria.  In  chlorination  processes,  getting  chlorine 

209 


EVERYMAN'S    CHEMISTRY 

into  combination  when  needed,  it  is  likely  that  light 
will  play  a  great  r61e.  Do  you  grasp  what  is  done  in 
this?  It  is  taking  power  direct  from  the  sun.  It  is 
getting  the  effect  direct  instead  of  waiting  throughout 
eons  of  years  for  energy  to  be  stored  by  means  of  chlo- 
rophyl  and  protoplasm  into  wood  and  wood  to  be 
reduced  to  coal.  It  is  doing  ourselves  what  nature 
does  for  us.  It  is  a  direct  reaction  gathered  in  from 
space.  How  far  shall  we  be  able  to  avail  ourselves  of 
this  illimitable  power?  Who  will  grasp  this  Might 
of  Day  and  master  it? 

GOLD. — The  robber  baron  would  not  associate  with 
common,  honest  folk;  he  held  aloof  from  them  and 
would  have  no  dealings  with  them  save  to  command. 
So  he  was  called  noble.  Gold  long  antedates  the  rob- 
ber barons,  but  it  obtained  its  title  to  nobility  in  the 
same  way.  It  does  not  combine  with  free  oxygen  or 
even  hydrogen  sulphide.  Acids  do  not  attack  it  as  a 
rule,  and  so  it  achieved  a  grand  reputation  as  the 
aristocrat  of  all  the  metals.  Another  likeness  to  the 
robber  barons  of  old  is  that  the  gold  strain  is  found 
everywhere;  there  are  traces  of  it  in  sea- water  to  the 
extent  of  about  three  and  one-half  grains  to  the  ton. 
Granite  contains  about  one  part  in  7,000,000,000,  and 
clays,  iron  pyrites,  and  nearly  all  silver,  copper,  zinc, 
lead,  bismuth,  tellurium,  and  antimony  ores  contain  it. 

In  the  mass  gold  is  yellow,  but  light,  reflected  from 
its  surfaces  many  times  before  it  reaches  the  eye,  is 
red.  Gold-leaf  is  green  or  blue  in  transmitted  light, 
and  if  precipitated  in  a  very  fine  state  of  subdivision 
the  tint  varies  from  red  to  dark  brown.  So  some 
gold  does  not  glitter. 

The  practice  of  chemistry  is  a  sport,  very  like 
hunting  wild  game.  As  soon  as  its  ways  are  well 

210 


SOME  OF  THE  RARER  METALS 

enough  known  the  game  is  likely  to  be  brought  down. 
Here  is  gold  with  all  its  far-famed  nobility,  and  yet 
even  the  medieval  alchemists  found  a  solvent  for  it 
in  what  they  called  aqua  regia,  a  mixture  of  nitric  and 
hydrochloric  acids.  Nitric,  hydrochloric,  or  sulphuric 
acid  alone  does  not  affect  it,  but  that  aqua-regia 
mixture  will  dissolve  it. 

Gold  chloride  is  soluble,  and  by  treating  this  with 
an  oxidizing  agent  oxides  of  gold  are  formed.  They 
are  not  very  stable,  and  so  far  no  great  use  has  been 
found  for  them,  but  there  they  are. 

Gold  is  obtained  in  a  number  of  different  ways. 
From  alluvial  deposits  the  very  heavy  metal  is  sepa- 
rated from  the  gravel.  Whether  this  is  done  in  pans  or 
"cradles"  by  hand,  or  in  great  sluices,  the  principle 
is  the  same.  The  gold  stays  while  the  gravel  is  washed 
away.  In  vein-bearing  mines  the  gold-bearing  quartz 
is  blasted  out  and  crushed  to  a  fine  powder  in  stamp- 
mills.  Then  the  powder  is  floated  in  troughs  as 
"slime"  over  copper  plates  amalgamated  with  mer- 
cury. Gold  is  very  soluble  in  mercury,  and  this  takes 
up  the  particles  as  the  slime  floats  on.  The  gold 
amalgam  is  scraped  off  and  the  mercury  removed  by 
distillation.  That  is  the  amalgamation  process. 

The  chlorination  process  is  used  in  connection  with 
sulphur-bearing  ores  such  as  pyrites.  The  ore  is  first 
roasted,  then  wet,  and  the  gold  is  extracted  with 
chlorine  which  goes  into  solution.  The  chloride  of 
gold  is  precipitated  by  means  of  hydrogen  sulphide, 
which  brings  the  gold,  but  only  the  gold,  back  to  the 
form  of  a  sulphide  again.  Then  the  sulphur  is  roasted 
away  and  the  gold  remains. 

The  cyanide  process  provides  that  the  powdered 
ore  be  leached  with  a  solution  of  cyanide  of  sodium, 
whiqh  dissolves,  the  gold  as  the  double  cyanide, 


EVERYMAN'S   CHEMISTRY 

NaAu(CN)2,  and  the  gold  is  precipitated  out  by  the 
addition  of  zinc  shavings  which  take  its  place  in  the 
soluble  cyanide. 

Colloidal  gold  is  a  suspension  of  particles  of  this 
heavy  metal  so  small  that  the  bombardment  of  the 
molecules  of  the  liquid  keeps  them  in  suspension.  It 
is  made  as  follows :  A  solution  of  about  one-hundredth 
of  one  per  cent. ,  or  less,  of  gold  chloride  is  made  slightly 
alkaline  by  adding  magnesia.  Then  a  few  drops  of  a 
mild  reducing  agent  that  will  take  up  the  chlorine,  such 
as  oil  of  turpentine  or  carbon  monoxide,  is  added  until 
the  solution  acquires  a  ruby-red  color — if  it  does. 
The  thing  is  tricky.  This  is  Faraday's  gold,  as  it  is 
sometimes  called,  or  colloidal  gold,  and  the  particles 
are  so  small  that  they  will  pass  right  through  filter 
paper.  It  is  red  because,  as  we  have  observed,  light 
reflected  backward  and  forward  from  many  surfaces 
of  gold  is  red;  and  this  condition  will  last,  with  the 
particles  constantly  dancing  about,  as  may  be  seen 
with  the  ultra-microscope,  for  an  indefinite  time.  But 
as  soon  as  you  add  an  electrolyte,  such  as  common 
salt  or  sulphuric  acid  or  caustic  soda,  the  red  color 
changes  first  to  blue,  then  to  violet,  then  to  black, 
and  finally  the  gold  particles,  having  coagulated,  set- 
tle down  on  the  bottom  of  the  vessel. 

Gold  is  too  soft  to  be  used  in  a  pure  state,  so  for 
coinage  in  Great  Britain  22  carats,  or  91.66%  per  cent, 
gold  and  8.33 %  per  cent,  copper  are  used.  The  mint  at 
Sydney,  Australia,  uses  silver  instead  of  copper,  so 
that  the  Sydney  sovereign  is  of  a  greenish  yellow.  In 
the  United  States,  France,  and  Germany  an  alloy  of 
90  per  cent,  gold  and  10  per  cent,  copper  is  used. 

Gold  is  the  standard  of  money,  and  it  is  not  a  very 
good  standard  because  it  fluctuates  in  value  itself. 
The  world's  production  of  gold  in  1915  was  22,758,808 

212 


SOME  OF  THE  RARER  METALS 

fine  ounces,  valued  at  $470,466,212,  of  which  the 
United  States  produced  4,887,604  fine  ounces,  valued 
at  $101,035,700.  The  world's  industrial  consumption 
of  gold  in  the  same  year  was  $66,651,860,  of  which  the 
United  States  consumed  one-half,  or  $35,736,700 
worth.  The  world's  production  of  gold  for  the  ten 
years  previous  to  1916  in  millions  of  fine  ounces  has 
been,  respectively,  56,  56,52,54,57,  60,  63,  67,  72,  75. 

PLATINUM  is  one  of  a  group  of  six  metallic  elements 
known  as  the  platinum  elements,  and  they  are  ruthen- 
ium (Ru) , rhodium  (Rh) ,  palladium  (Pd) ,  osmium  (Os) , 
indium  (Ir),  and  platinum  (Pt).  They  are  all  silvery 
white  and  lustrous,  chemically  inert,  and  exceedingly 
rare.  The  great  value  of  platinum  is  in  part  due  to  the 
fact  that  it  is  not  attacked  by  air  and  strong  acids 
and  the  very  high  temperature  at  which  it  fuses,  so 
that  chemists  need  dishes  and  crucibles  made  of  the 
metal.  On  the  other  hand,  alkalies  do  attack  it,  and 
it  makes  alloys  with  other  metals  like  lead,  silver,  and 
zinc,  so  that  the  chemist  does  not  like  to  let  the  labo- 
ratory boy  make  free  with  his  expensive  platinum 
ware.  It  has  about  the  same  coefficient  of  expansion 
as  glass,  so  that  it  is  fused  in  glass  to  make  gas-tight 
joints.  Alloys  of  cheaper  metals  have,  however,  been 
devised  which  also  accomplish  this  purpose. 

When  platinum  is  precipitated  from  solutions  of 
platinum  tetrachloride,  PtCU,  a  velvety  black  powder 
of  pure  platinum  is  obtained  which  is  called  platinum 
black.  When  ammonium  chloroplatinate  is  calcined 
the  metal  that  remains  behind  resembles  coke  in  ap- 
pearance and  this  is  called  platinum  sponge.  If  as- 
bestos is  soaked  in  PtCl4  and  ignited,  the  asbestos 
permeated  with  platinum  is  called  platinized  asbestos. 
These  are  the  forms  in  which  it  is  frequently  used  in 

213 


EVERYMAN'S    CHEMISTRY 

industry.  In  finely  divided  states  all  metals  of  this 
group  have  the  faculty  of  absorbing  vast  quantities 
of  certain  gases;  of  drawing  a  film  of  the  gas  to  sur- 
round every  particle.  This  seems  to  be  the  reason 
why  they  are  of  great  value  in  catalysis.  Platinized 
asbestos,  you  may  recall,  is  used  as  the  catalyst  in  the 
contact  process  for  the  manufacture  of  sulphuric  acid. 
It  is  a  great  pity  that  these  metals  are  so  dear. 

MERCURY. — You  can't  pick  it  up,  and  that  is  a  good 
way  to  prove  that  it  is  a  liquid.  It  is  useful  in  amal- 
gamating gold  from  its  ores  because  gold  is  very  solu- 
ble in  it,  and  of  course  it  is  used  for  thermometers  and 
barometers  and  in  certain  chemical  industries.  A 
liquid  over  thirteen  times  as  heavy  as  water  naturally 
has  its  uses. 

It  is  found  in  nature  chiefly  as  the  sulphide,  and  mere 
heating  is  enough  to  drive  the  sulphur  out  of  com- 
bination, leaving  the  metal  free.  The  sulphide  is 
known  as  cinnabar  and  vermilion,  and  it  is  a  grand 
red  paint  unless  it  comes  in  contact  with  white  lead, 
when  the  black  lead  sulphide  is  produced,  as  we  have 
noticed  elsewhere.  Mercury  has  two  methods  of 
combining,  as  monovalent  and  divalent — that  is,  with 
one  bond  and  with  two.  When  one  bond  is  engaged 
the  compounds  are  mercurous;  when  two,  they  are 
called  mercuric.  Mercurous  oxide  is  Hg2O,  and  mer- 
curic oxide  is  HgO.  If  the  latter  is  heated  we  get  free 
oxygen  and  mercurous  oxide: 

2HgO  =  Hg20  +  O 

If  mercury  is  ground  up  with,  for  instance,  milk 
sugar  it  becomes  divided  into  very  fine  globules,  and 
these  have,  as  we  were  reminded  under  the  head  of 
colloidal  chemistry,  a  much  greater  surface  in  propor- 

214 


SOME  OF  THE  RARER  METALS 

tion  to  the  volume  thanf  the  metal  has  in  bulk.  This 
is  the  way  blue-pills  are  prepared,  and  the  mercury 
has  in  this  form  an  activity  which  is  lacking  in  larger 
masses. 

Mercurous  chloride,  HgCl,  is  calomel. 

Mercuric  chloride,  or  bichloride  of  mercury,  HgCl2, 
is  corrosive  sublimate.  The  relation  here  is  a  little 
too  close  for  safety,  because  either  salt  may  be  pre- 
pared from  the  other.  For  instance,  like  silver  chlor- 
ide, the  mercurous  chloride  (calomel)  is  darkened  by 
light,  and  chlorine  is  liberated,  but  it  proceeds  to 
abuse  its  freedom  by  turning  part  of  the  calomel  into 
corrosive  sublimate: 

HgCl     +    Cl     =       HgCl2 
calomel        chlo-        corrosive 
line         sublimate 

Mercurous  chloride  is  used  in  medicine  because  it 
stimulates  certain  organs  in  producing  secretions,  but 
care  must  always  be  taken  that  it  does  not  go  over  to 
the  mercuric  form  and  thus  become  the  poisonous 
bichloride. 

Fulminate  of  mercury  is  obtained  when  mercury  is 
treated  with  nitric  acid  and  alcohol  is  added  to  the 
solution.  The  formula  is  Hg(ONC)2-  It  decomposes 
suddenly  when  struck,  and  is  used  in  making  percus- 
sion caps.  It  is  a  white  precipitate. 

The  thiocyanate  is  another  interesting  salt.  Potas- 
sium thiocyanate,  K(SCN),  will  precipitate  it  from  a 
solution  of  a  mercuric  salt.  When  formed  into  little 
balls  and  burned  in  the  air  they  have  a  voluminous  ash 
and  are  known  as  "Pharaoh's  Serpents'  Eggs." 

RADIUM. — In  1896,  Becquerel  discovered  that  a  pho- 
tographic plate  inclosed  in  an  envelope  of  black  paper 
which  keeps  out  the  light  was  affected  as  though  light 
15  215 


EVERYMAN'S    CHEMISTRY 

had  struck  it  when  a  compound  of  uranium  was 
brought  into  contact  with  it.  He  also  discovered  that 
the  air  in  the  immediate  vicinity  of  a  compound  of 
uranium  became  a  good  conductor  of  electricity — be- 
came ionized — whereas  otherwise  it  was  not.  Now 
this  quality  of  uranium  compounds  is  proportional  to 
the  amount  of  uranium  in  it.  But  uranium  ores  were 
discovered  to  be  four  times  as  active  as  the  uranium  it- 
self. This  led  Professor  and  Mme.  Curie  to  the  discov- 
ery that  the  pitchblende  residues  from  which  the  urani- 
um had  been  extracted  were  also  active.  After  working 
over  a  ton  of  such  residues  and  eliminating  that  which 
was  not  active  m  this  manner,  they  found  the  quality 
to  abide  in  the  barium  chloride  in  which  they  could 
discover  no  other  element  by  the  ordinary  chemical 
tests,  and  they  found  that  it  was  sixty  times  as  active 
as  uranium.  The  percentage  of  chlorine  was  very 
nearly  that  to  be  expected  in  barium  chloride,  and  yet 
this  was  not  like  any  other  barium  chloride;  it  had 
this  remarkable  photo-activity  and  it  ionized  the  air 
so  that  it  became  a  conductor  of  electricity.  So  this 
man  and  wife  in  their  laboratory  purified  and  crystal- 
lized and  recrystallized  their  barium  chloride  until 
they  separated  out  a  new  compound  that  contained 
less  chlorine  proportionately  than  barium  chloride 
and  showed  an  entirely  different  spectrum.  It 
proved  to  be  bivalent,  to  have  an  atomic  weight  of 
226.5,  and  took  thereby  a  vacant  place  in  the  periodic 
table.  Its  activity  from  a  photochemical  standpoint 
and  its  capacity  to  ionize  the  air  proved  to  be  three 
million  times  as  great  as  that  of  uranium.  So  they 
called  it  radium,  from  its  disposition  to  emit  rays. 

Now  the  chemical  reactions  of  barium  and  radium 
chlorides  are  so  much  alike,  and  they  are  always  found 
together,  so  that  the  only  way  to  get  them  apart  is 

216 


SOME  OF  THE  RARER  METALS 

by  taking  advantage  of  their  different  degrees  of  solu- 
bility. By  means  of  electrolysis  a  minute  quantity 
of  a  white  metal,  which  is  radium,  has  been  prepared. 
It  melts  at  700°,  turns  black  in  the  air,  chars  paper, 
and  dissolves  readily  in  water  and  dilute  hydrochloric 
acid. 

The  properties  of  radium  which  upset  so  many  of  the 
theories  in  regard  to  the  permanency  of  matter  are  due 
to  the  fact  that  it  is  constantly  giving  off  of  its  sub- 
stance with  the  development  of  heat.  One  gram  of 
radium,  which  is  about  fifteen  and  one-half  grains  Troy 
weight,  would  produce  the  same  amount  of  heat,  if  de- 
veloped spontaneously,  as  would  be  caused  by  the 
combustion  of  300  kilograms  of  hydrogen.  Nothing 
else  is  known  to  develop  such  heat.  It  comes  from  the 
disintegration  of  the  atom.  If  this  could  be  brought 
about  artificially  with  other  elements,  say  with  carbon, 
a  bucketful  of  coal  would  propel  a  ship  across  the  sea — 
if  the  ship  were  not  too  big  and  the  sea  were  not  too 
wide.  These  rays  do  all  sorts  of  tricks.  They  incite 
luminosity  in  diamonds,  rubies,  fluorspar,  calcium 
sulphide,  zinc  sulphide,  and  a  number  of  other  bodies. 
Luminous  watches  and  clocks  now  have  the  hours 
painted  on  with  a  coating  of  zinc  sulphide  with  which 
an  absurdly  small  amount  of  radium  bromide  has  been 
mixed.  In  the  dark  they  glow  with  a  greenish  light. 
If  a  tube  of  radium  salt  is  held  before  your  fore- 
head, you  can  see  the  light  through  your  closed  eye- 
lids— but  this  is  not  an  experiment  to  be  recommended. 
If  you  carry  a  tube  of  radium  bromide  in  your  pocket 
for  a  few  hours  you  will  suffer  from  painful  sores  that 
are  very  slow  to  heal.  The  rays  discolor  paper,  turn 
oxygen  into  ozone,  reduce  bichloride  of  mercury 
(HgCl2)  to  calomel  (HgCl),  and  are  about  the  busiest 
mites  in  nature. 

217 


EVERYMAN'S    CHEMISTRY 

Three  kinds  of  rays  are  given  forth;  and  if  a  strong 
magnet  is  held  above  a  piece  of  radium  salt,  alpha 
rays  will  go  to  the  negative  pole,  being  positively 
charged,  beta  rays  will  go  to  the  positive  pole,  being 
negatively  charged,  and  the  gamma  rays  are  not 
affected — they  go  right  on.  For  this  experiment  the 
salt  is  put  into  an  open  lead  container,  as  lead  is  more 
resistant  to  the  rays  than  other  bodies. 

The  alpha  rays  are  projected  at  a  velocity  of  20,000 
miles  a  second,  but  they  have  slight  penetrative  power. 
Even  the  resistance  of  a  few  cubic  centimeters  of  air 
is  too  much  for  them.  They  appear  to  be  positively 
charged  electrons. 

The  beta  rays  appear  to  be  negatively  charged  elec- 
trons, and  have  more  speed  than  the  alpha  rays.  They 
are  projected  from  the  radium  salt  with  a  velocity 
approaching  100,000  miles  a  second.  Their  properties 
correspond  with  the  cathode  rays  of  a  Crookes  tube, 
but  they  do  not  travel  quite  so  fast. 

The  gamma  rays  have  an  intense  penetrative  power 
and  are  very  similar  to,  if  not  identical  with,  the  Roent- 
gen or  X-rays.    Tested  in  aluminium,  the  penetrative 
powers  of  the  three  types  of  rays  are  as  follows : 
alpha  :  beta  :  gamma  :   :  10:     1,000  :  100,000. 

A  great  deal  has  been  said  about  the  use  of  radium 
in  curing  cancer.  The  matter  is  still  in  dispute.  If 
the  rays  are  really  Roentgen's  X-rays,  it  would  seem 
to  be  beating  a  long  way  about  the  bush  to  get  them 
from  radium.  But  this  is  no  place  for  the  discussion. 
No  authority  regards  radium  as  a  sure  cure  for  all 
malignant  growths. 


XVIII 

CARBON 

Diamonds — Graphite  and  Amorphous  Carbon — Moissan's  Artificial 
Diamonds — Acheson's  Graphite  Preparations — Uses  of  Graphite 
— Lead-pencils — Charcoals — Fuels  of  Many  Kinds — Gas-engines 
— More  About  Fuels — Different  Kinds  of  Gas — Present  Waste — 
Improvements  Possible  and  Desirable — Carbonic  Acid,  and  a 
Few  Carbon  Compounds 

CARBON  is  by  far  the  most  profoundly  studied  of 
all  the  elements  and  it  almost  seems  as  though  less 
were  known  about  it  than  any  other.  Of  all  the  many 
compounds  recorded  in  chemistry,  over  half  of  them 
are  combinations  of  carbon.  Everything  that  has  life 
contains  it.  The  carbon  molecule  is  large — how  large 
is  not  clear,  but  it  must  have  at  least  twelve  atoms 
in  its  simplest  form.  Like  interesting  persons,  it  is 
not  always  the  same — it  is  pure  carbon  as  the  diamond, 
as  graphite,  and  as  a  black,  amorphous  powder.  An- 
thracite coal  is  75  to  90  per  cent,  pure  carbon,  and  the 
rest  of  it  is  carbon  in  combination  principally  with 
hydrogen  and  with  minerals,  such  as  lime,  etc.,  which 
show  in  the  ash.  Let  us  consider  first  the  states  or 
allotropic  modifications  in  which  carbon  is  known  in  a 
free  state. 

The  diamond  is  the  hardest  substance  we  know; 
it  will  scratch  any  other  surface.  In  the  old  adage, 
"Diamond  cut  diamond,"  it  is  indicated  that  each 
both  cuts  and  gives  way.  It  resists  the  strongest 

219 


EVERYMAN'S    CHEMISTRY 

oxidizing  agents,  as,  for  instance,  a  mixture  of  nitric 
acid  and  chlorate  of  potash;  and  it  has  no  interest 
whatever  in  acids  or  alkalies;  they  do  not  affect  it. 
It  would  appear  to  be  the  form  that  carbon  takes  on 
when  it  wants  to  be  left  severely  alone,  chemically. 
Of  course,  the  diamond  miner  may  get  it  and  you  may 
buy  it  in  a  ring  for  your  wife,  and  a  thief  may  steal 
it,  all  of  which  does  not  interest  the  diamond  at  all. 
Chemically  speaking,  it  is  being  left  to  itself  when  it 
is  stolen.  On  the  other  hand,  if  you  try  to  bring  it 
into  combination  with  other  elements,  it  will  show 
how  inert  it  is — unless  you  know  the  tricks,  unless 
you  are  familiar  with  that  strategy  which  is  the  sub- 
stance of  research  in  science.  Then  you  become  the 
master  and  the  diamond  is  no  more  inert.  In  this  case, 
all  you  have  to  do  is  to  heat  the  diamond  to  redness 
and  dip  it  into  a  flask  containing  oxygen.  Then  the 
diamond  will  burn  with  a  bright  flame,  just  like  any 
piece  of  coal.  Examine  the  gas  that  proceeds  from  this 
combustion  and  you  prove  the  diamond  to  be  carbon, 
for  the  gas  is  carbon  dioxide,  CO2,  and  nothing  else. 
Lead  it  through  lime-water  and  down  comes  the  white 
precipitate  of  carbonate  of  lime,  or  marble.  Here  is 
another  chance  for  a  modest  millionaire  to  construct 
for  himself  a  marble  gravestone  made  of  lime  and 
diamonds. 

If  a  diamond  is  subjected  to  a  very  high  tempera- 
ture in  the  absence  of  air,  it  turns  to  graphite.  The 
diamond  is  a  very  poor  conductor  of  heat  and  elec- 
tricity. 

Moissan,  a  French  chemist,  made  diamonds  arti- 
ficially in  1893  by  dissolving  pure  carbon  made  from 
sugar  (which  is  a  compound  of  carbon,  hydrogen,  and 
oxygen)  in  molten  iron  in  an  electric  furnace  at  about 
3,000°  centigrade,  and  then  cooling  it  suddenly  by 

220 


CARBON 

pouring  the  mass  into  a  hole  drilled  into  a  copper 
block  which  was  cooled,  and  covering  the  cavity  with 
an  iron  stopper.  When  it  had  cooled,  the  metal  was 
dissolved  away  by  an  acid,  and  there  remained  very 
small  diamonds,  precisely  like  the  rough  diamonds 
found  in  the  mines  in  their  crystal  form,  hardness,  etc., 
and  they  displayed  the  same  rounded  edges  and 
angles.  No  one  has  succeeded  in  producing  diamonds 
of  any  appreciable  size. 

Graphite  is  also  crystallized  carbon.  Unlike  the 
diamond,  it  is  very  soft  and  opaque,  and  it  is  a  very 
good  conductor  of  heat  and  electricity.  It  occurs 
in  nature  and  is  made  artificially  by  heating  Pennsyl- 
vania anthracite  coal  finely  powdered  in  an  electric 
furnace.  It  has  very  wide-spread  use.  Remember, 
this  is  carbon,  just  like  the  diamond,  but  there  is  a 
difference  in  the  arrangement  of  the  atoms  in  their 
molecules.  When  two  bodies  differ,  there  must  be  an 
external  or  internal  reason  for  the  difference,  whether 
we  know  it  or  not.  Graphite  is  exceedingly  inert  at 
high  temperatures,  and  you  cannot  make  Moissan's 
little  diamonds  by  using  graphite  instead  of  sugar 
charcoal.  It  will  withstand  any  heat  we  can  produce, 
and  it  remains  graphite.  But  if  you  treat  graphite 
with  a  mixture  of  dry  potassium  chlorate  and  very 
strong  nitric  acid,  it  turns  to  a  yellow  crystalline  sub- 
stance called  graphitic  acid,  CnH^Os,  which,  when  it 
is  heated,  decomposes  explosively  and  yields  very  fine 
amorphous  carbon.  It  is  a  little  too  explosive  to  en- 
courage close  study.  The  diamond,  you  remember, 
is  not  affected  by  the  same  reagents. 

One  of  the  greatest  uses  of  graphite  is  for  making 
pots  or  crucibles  for  crucible  steel  and  for  other  chem- 
ical reactions  in  which  high  temperatures  prevail. 
Its  physical  and  chemical  inertia  is  what  gives  it  its 

221 


EVERYMAN'S    CHEMISTRY 

value  for  this.  Another  great  use  is  for  electrodes  for 
the  same  reason,  in  electric  steel  furnaces  and  in 
fixing  or  combining  nitrogen  of  the  air  as  well  as  for 
other  purposes  in  electro-chemistry.  Then  it  is  a 
wonderful  lubricant,  being  as  smooth  and  unctuous 
as — some  men  we  know.  When  chemistry  grows 
popular  and  anybody  is  referred  to  as  being  "as  smooth 
as  graphite,"  we  shall  know  that  butter  will  not  melt 
in  his  mouth  and  that  he  is  so  oily  that  he  will  slip  in 
anywhere  and  that  there  is  never  any  squeak  or  cry 
when  he  is  having  his  own  way.  Dr.  E.  G.  Acheson, 
who  invented  carborundum,  discovered  that  by  treat- 
ing finely  ground  artificial  graphite  with  a  solution  of 
tannin  or  any  one  of  several  organic  compounds,  it 
takes  on  such  a  fine  subdivision  of  its  particles  that 
they  pass  through  filter  paper  and  remain  suspended 
when  mixed  with  water  or  oil.  He  calls  this  form 
' '  deflocculated  graphite,"  and  gave  to  the  mixture  with 
water  the  trade  name  of  "aquadag."  It  is  used  to 
aid  in  cutting  metals  in  machine-shops.  Mixed  with 
oil,  he  calls  it  "oildag,"  which  is  a  valuable  lubricant. 
A  cheap  oil  mixed  with  deflocculated  graphite  will  do 
the  work  of  a  high-grade  lubricating  oil  for  the  same 
purpose. 

Lead-pencils  are  not  made  of  lead  at  all.  Graphite 
does  the  business.  The  natural  graphite  is  first  freed 
from  the  mica  and  sand  with  which  it  is  usually  found, 
and  then  mixed  with  clay  that  has  also  been  freed 
from  all  grit.  The  mixture  is  ground  with  water  be- 
tween millstones  and  passed  between  rolls  and  through 
a  mixer  and  then  squeezed  through  a  die  in  the  form 
of  a  rod.  This  is  dried  and  baked  at  a  high  tempera- 
ture for  the  purpose  of  toughening  the  so-called 
"leads."  They  are  then  inclosed  in  wood,  and  there 
are  your  pencils.  The  more  graphite  in  proportion  to 

222 


CARBON 

the  clay  the  softer  and  blacker  is  the  pencil;  the 
greater  the  proportion  of  clay  to  graphite  the  harder 
and  lighter  the  pencil.  A  similar  process  takes  place 
in  hardening  the  clay  in  the  leads  of  lead-pencils  to 
that  which  occurs  in  making  brick;  in  fact,  the  lead 
in  a  lead-pencil  is  a  mixture  of  brick  and  graphite. 
Nothing  happens  to  the  graphite  in  making  lead-pen- 
cils; it  stays  where  it  is  put  until  it  is  rubbed  off  on 
the  paper. 

AMORPHOUS  CARBON. — This  is  an  indefinite  name 
because  under  it  we  must  consider  the  approximately 
but  not  really  pure  amorphous  carbons  such  as  coke, 
charcoal,  bone-black,  lampblack,  etc.,  and  go  into 
a  discussion  of  fuels  which  range  from  anthracite  coal, 
which  contains  the  most  carbon,  always  mixed  with 
some  minerals,  over  to  peat  and  wood,  in  which  all 
the  carbon  is  in  combination.  Pure  amorphous  carbon 
is  not  found  in  nature  so  far  as  the  writer  knows. 
Let  us  first  address  ourselves  to  some  of  the  char- 
coals before  we  take  up  the  greater  problem  of  fuels. 

Wood  charcoal  is  produced  by  burning  wood  with 
the  air  so  shut  out  from  access  to  the  fire  that  only 
the  hydrocarbons  which  burn  most  readily  are  con- 
sumed, leaving  the  more  or  less  pure  carbon,  driven 
out  of  the  cellulose  of  which  the  cells  of  the  wood  are 
composed,  unconsumed  behind.  It  is  very  porous 
and  can  condense  large  quantities  of  gases  in  its  pores. 
For  instance,  it  will  take  up  ninety  times  its  own 
volume  of  ammonia.  When  heated  it  will  give  the 
gas  off  again. 

What  appears  to  happen  is  that  the  gas  is  adsorbed ; 
that  is,  that  upon  every  minute  filament  of  the  char- 
coal a  coating  of  the  gas  adheres. 

Some  day  let  us  hope  that  the  adsorption  of  gases 

223 


EVERYMAN'S    CHEMISTRY 

may  lead  us  into  the  study  and  final  understanding 
of  the  sense  of  smell.  If  any  one  asks  us  what  makes 
things  smell,  we  must  answer  that  we  do  not  know, 
but  we  have  this  one  point — that  odoriferous  gases 
seem  to  be  adsorbed  by  charcoal.  This  may  have 
been  studied  at  length,  but  I  do  not  know  of  it.  Smell 
is  the  Cinderella  of  the  senses,  and  we  should  know 
much  more  about  it  than  we  do. 

Bone-black  is  obtained  by  heating  bones  away  from 
air.  It  is  then  treated  with  hydrochloric  acid,  to  re- 
move the  phosphates  and  carbonates.  It  has  the 
power  of  absorbing  coloring  matter,  and  many  evil- 
smelling  substances  from  liquids,  and  also  certain 
salts,  as,  for  instance,  the  salts  of  lead.  It  is  also 
called  "animal  charcoal,"  and  is  used  in  water-filters 
and  in  sugar-refineries  to  decolorize  the  sugar  liquids. 
Mixed  with  linseed-oil  it  becomes  the  artist's  "ivory 
black" — except  when  lampblack  is  employed  in  the 
place  of  it. 

Lampblack  is  made  by  burning  natural  gas  or  pe- 
troleum residue  and  catching  the  black  smoke.  This 
''carbon  black "  is  chiefly  used  for  black  ink  and  paint. 

Coke  is  the  great  fuel  of  the  iron  and  steel  industry, 
and  at  the  mere  mention  of  it  we  Americans  might 
well  hang;  our  heads  in  shame.  To  make  coke  we  distil 
the  hydrocarbons  out  of  coal,  leaving  the  compara- 
tively pure,  spongy  carbon  behind.  It  may  be  done  in 
two  ways — by  what  are  known  as  beehive  coke-ovens, 
whereby  the  coke  is  saved  and  everything  else  burned 
up  or  allowed  to  escape;  and  by  by-product  ovens, 
whereby  the  coke  is  saved  and  so  are  the  valuable  by- 
products. These  by-products  are  a  vast  amount  of  gas 
available  for  power;  ammonia,  needed  as  fixed  nitro- 
gen in  sulphate  of  ammonia  by  the  farmers;  benzol, 
toluol,  and  other  hydrocarbons  available  for  making 

224 


CARBON 

dyestuffs,  explosives,  medicines,  and  a  whole  list 
of  chemical  products,  as  well  as  being  useful  to 
operate  explosion  engines  in  the  same  manner  as 
gasolene;  phenol  or  carbolic  acid  for  disinfecting 
and  for  chemical  manufacture;  tar  and  pitch  for  roofs 
— and  many  other  bodies.  Doesn't  it  seem  wrong  to 
burn  up  these  useful  products?  And  yet  even  now, 
with  a  great  rush  and  hurry  to  build  by-product  ovens, 
fully  half  of  the  coke  produced  in  the  United  States 
is  still  made  in  the  wasteful  beehive  ovens.  We  may 
talk  as  we  please  about  supply  and  demand,  and 
reasons  why  and  convenience,  and  all  sorts  of  things, 
but  some  day  we  are  bound  to  come  to  a  clearer  con- 
ception of  the  maxim  that  Waste  makes  Want.  Some 
day,  unless  we  go  to  pieces  and  lose  our  arts  and 
sciences  and  take  to  the  woods  again  like  Indians,  we 
shall  have  a  sense  of  the  fact  that  future  generations 
have  some  rights,  and  that  these  precious  hydro- 
carbons, that  it  has  taken  nature  hundreds  of  thou- 
sands of  years  to  produce,  should  not  be  idly  de- 
stroyed as  though  we  were  a  nation  of  drunken  sailors. 
There  is  no  use  in  growing  angry  or  in  blaming  any- 
body for  this  cataclysmic  waste;  but  now  that  we 
know  better  it  is  time  to  stop  it. 

Coke  is  a  grand  fuel  and  should  be  used  more  than 
it  is.  In  the  first  place,  if  made  in  by-product  coke- 
ovens  or  in  gas-works,  it  has  already  been  used  to 
good  purpose,  so  that  it  isn't  all  waste.  It  burns 
rapidly  to  good  effect,  giving  heat  when  it  is  needed. 
Being  much  purer  carbon  than  ordinary  coal,  it  is  used 
in  industries. 

Anthracite  coal  contains  about  95  per  cent,  of 
carbon,  either  free  or  combined,  and  is  also  a  good 
fuel  in  that  it  burns  with  but  little  ash.  Ash  is  chiefly 
the  mineral  content  of  coal. 

225 


EVERYMAN'S    CHEMISTRY 

Bituminous  coal  contains  So-odd  per  cent,  of  carbon, 
but  unless  it  is  properly  fired  a  great  waste  takes  place. 
It  is  also  a  pity  to  burn  up  the  valuable  hydrocarbons 
which  it  contains,  and  it  is  dirty  and  sooty  and  makes 
the  smoke  nuisance. 

With  the  improvements  that  are  being  made  in  the 
burning  of  powdered  coal  in  an  air-blast  it  is  prob- 
able that  ere  long  most  coal  will  be  consumed  in  this 
manner.  The  art  has  been  developed  from  the  need 
of  a  very  hot  flame  for  cement  manufacture,  and  it  is 
already  being  proposed  for  firing  boilers  with  consid- 
erable saving.  The  only  thing  that  holds  it  back  is 
that  the  heat  is  so  intense  that  it  destroys  the  boiler- 
plates. The  coal  must  be  ground  just  as  it  is  fed  into 
the  boiler  because  in  a  finely  powdered  form  coal  is 
liable  to  spontaneous  combustion  and  it  is  also  ex- 
plosive. So  in  burning  coal  powder  (much  finer  than 
anthracite  culm)  it  is  blown  into  the  fire  just  as  it  is 
ground.  In  other  words,  the  coal-mill  operates  as  the 
fire  is  fed.  There  is  no  smoke  and  no  soot.  The  com- 
bustion is  complete  to  CO2.  It  is  clean,  and  the  full 
heat  of  the  coal  is  developed.  Now  if  the  inventive 
genius  of  engineers  is  not  able  to  meet  these  problems 
before  the  next  generation  comes  along,  they  should 
be  spanked  and  sent  to  bed.  Think  what  it  means: 
much  greater  efficiency  of  coal  and  no  more  smoke 
nuisance!  It  is  bound  to  come,  with  only  a  few  little 
inventions  needed. 

The  gas-engine,  in  which  the  power  As  ootained  by 
explosion  within  the  cylinder  of  producer  gas  and  air, 
or  of  gaseous  hydrocarbons  and  air,  is  supplanting  the 
steam-engine  in  many  places.  Although  more  ex- 
pensive to  build,  install,  and  operate,  and  composed  of 
more  parts  than  the  steam-engine,  it  is  more  econom- 
ical in  principle  and  already  more  economical  in  prac- 

226 


CARBON 

tice  in  some  places.  Modern  blast-furnace  practice 
calls  for  gas-engines  for  the  blowers. 

Lignite  coal  contains  60  to  70  per  cent,  of  carbon; 
peat,  50  to  60  per  cent. ;  and  wood,  about  50  per  cent. 

Liquid  fuels  are  gasolene,  about  the  lightest  of  the 
liquid  petroleum  bodies;  kerosene,  which  is  less  vola- 
tile; crude  oil;  and  petroleum  refuse.  The  term  fuel 
oil  in  current  use  indicates  any  petroleum  product 
available  for  fuel,  but  it  is  understood  to  be  freed  from 
gasolene.  The  present  value  of  gasolene  assures  this, 
and  the  expression  generally  represents  those  petro- 
leum products  for  which  no  better  market  outlet  may 
be  obtained.  We  need  not  discuss  them  in  detail; 
they  are  all  hydrocarbons,  and  are  used  or  not  for  fuel, 
according  to  the  price.  Alcohol  is  at  present  used  as 
a  fuel  on  a  very  small  scale.  Its  use  may  increase  as 
the  art  of  making  it  from  wood  waste  and  other  refuse 
is  developed,  or  if  better  methods  for  denaturing  it  are 
discovered.  As  things  are,  the  present  laws  governing 
the  production  of  alcohol  make  the  most  economical 
manufacture  impossible.  It's  too  bad  that  so  much 
may  be  honestly  said  against  alcohol,  which  has  also 
so  many  useful  qualities.  It  burns  with  such  a  clean 
flame  that  it  is  the  most  agreeable  of  all  fuels.  The 
manufacture  of  alcohol  from  wood  waste,  such  as  saw- 
dust, etc.,  has  passed  the  stage  of  preliminary  experi- 
ment and  is  now  in  operation  in  a  limited  way.  The 
trick  has  been  turned;  it  is  an  economical  achieve- 
ment. 

GASEOUS  FUELS. — Coal-gas  is  obtained  by  heating 
soft  coal  without  access  of  air.  The  by-products, 
which  are  similar  to  those  of  the  coke  industry,  are 
conserved,  and  the  gas,  sold  for  illumination  and 
cooking,  contains  nearly  50  per  cent,  of  hydrogen  and 

227 


EVERYMAN'S   CHEMISTRY 

over  40  per  cent,  of  methane,  CH4,  and  about  6  per 
cent,  of  carbon  monoxide.  There  are  a  great  many 
other  hydrocarbons  contained  in  it  in  small  amounts. 
Water-gas  is  made  by  heating  coke  to  a  high  tem- 
perature by  blowing  a  blast  of  air  over  it ;  then  steam 
is  blown  over  the  white-hot  fuel,  whereby  the  water 
is  decomposed  and  carbon  monoxide  is  formed,  to- 
gether with  free  hydrogen — both  combustible  gases; 

c    +    H2o    =    co    +    H2 

coke        steam        carbon      hydro- 
monox-        gen 
ide 

But  both  of  these  gases  burn  with  a  blue  flame,  so 
that,  to  make  the  gas  illuminating,  " gas-oil "  or  "solar 
oil"  from  petroleum  is  blown  in  and  brought  to  a 
high  temperature  with  a  view  to  converting  the  liquid 
hydrocarbons  permanently  into  gases.  Water-gas  has 
less  heating  value  than  coal-gas,  but  it  is  cheaper  to 
produce.  Most  large  gas  companies  make  both  kinds. 

PRODUCER  GAS. — This  is  used  chiefly  for  gas- 
engines  and  as  a  furnace  fuel.  It  is  made  by  passing 
air  through  incandescent  coke  or  coal,  but  not  in  suf- 
ficient quantity  to  insure  complete  combustion  and 
thus  produce  carbon  dioxide,  CO2,  which  will  not 
burn.  Only  enough  air  is  passed  through  to  produce 
carbon  monoxide,  CO,  which,  mixed  with  a  great  deal 
of  nitrogen,  is  the  chief  constituent  of  producer  gas. 
Sometimes  steam  is  blown  in  with  the  air,  decompos- 
ing the  water  and  thus  adding  hydrogen  and  oxygen 
to  the  gas.  The  gas  has  a  low  heat  value,  but  it  is 
very  cheap  to  produce. 

By-product  gas  producers  provide  for  the  recovery 
of  the  nitrogen  contained  in  the  coal  by  injecting 

228 


CARBON 

steam  into  the  coal-bed  of  the  producer.  The  oxygen 
and  hydrogen  of  the  steam  are  torn  apart  by  the  heat, 
and  the  hydrogen  combines  with  the  nitrogen  fixed  in 
the  coal  to  form  ammonia,  NH3.  Leading  this  into 
sulphuric  acid  produces  ammonium  sulphate.  In  Eng- 
land these  by-product  producers  are  largely  used  on 
low-grade  or  high-ash  coals. 

NATURAL  GAS  comes  from  the  petroleum  districts 
and  is  chiefly  methane,  CH4.  We  shall  discuss  this 
gas  later. 

ACETYLENE,  C2H2,  is  a  gas  of  very  high  illuminat- 
ing power  now  produced  by  the  action  of  water  upon 
calcium  carbide,  CaC2: 


CaC2     +    2H20     =     CjHj    +    Ca(OH)2 
calcium          water        acetylene  lime 

carbide 

It  is  explosive  with  almost  any  mixture  of  air. 

Before  we  leave  the  subject  of  gas  let  us  do  a  little 
prophesying.  Most  municipalities  require  gas  sold 
to  residents  to  have  a  certain  candle-power  in  order 
that  a  lighted  jet  shall  give  not  less  than  a  designated 
measure  of  light.  But  since  it  is  much  more  econom- 
ical to  burn  gas  in  incandescent  mantles  which  require 
only  heat  to  make  them  glow,  and  no  colored  flame  at 
all,  there  is  no  use  in  demanding  a  standard  of  candle- 
power.  The  requirement  should  be  not  twenty-two 
candle-power,  but  so  many  "B.T.U.,"  as  British 
thermal  units  are  called;  in  other  words,  it  should 
produce  a  given  amount  of  heat  instead  of  a  given 
amount  of  light.  That  would  give  us  gas  burning  with 
a  blue  flame  but  more  efficient  with  Welsbach  mantles 
and  for  heating,  and  the  cost  of  enriching  it  to  make 

229 


EVERYMAN'S    CHEMISTRY 

a  bright  light  by  injecting  hydrocarbons  would  be 
removed.  It  would  give  us  much  cheaper  gas  and 
would  serve  instead  of  coal  for  nearly  all  municipal 
uses.  It  would  do  away  with  the  smoke  nuisance, 
save  the  by-products,  and,  as  gas  could  be  conveyed 
by  pipe-lines  over  the  country,  be  distributed  from 
coke-ovens  to  any  place  where  it  was  needed.  Then 
the  ugly  factory  chimneys  might  be  torn  down  and 
the  clouds  of  smoke  and  rain  of  soot  would  disappear. 
It  is  bound  to  come. 

We  are  also  sure  to  come  some  day  to  the  problem 
of  using  high-ash — that  is,  low-grade — coals.  Enor- 
mous quantities  of  these  coals  are  common  in  the  coal- 
fields, but  nobody  wants  to  bother  with  them.  In  by- 
product producers,  however,  they  can  be  burned  for 
their  gas,  and  this  used  for  the  generation  of  electric 
power  which  may  be  transmitted  considerable  dis- 
tances. High-ash  coal  does  not  produce  good  coke. 
The  ammonia  and  other  by-products  will  be  saved. 

Our  present  methods  of  wasting  coal  and  befouling 
the  air  are  not  quite  civilized  in  the  light  of  present 
knowledge.  According  to  the  statistics  of  the  United 
States  Geological  Survey,  there  were  266,204,248,000 
cubic  feet  of  artificial  gas  made  in  the  United  States 
in  1915,  valued  at  $173,832,132.  This  is  an  increase 
of  25  per  cent,  in  quantity  and  13  per  cent,  in  value 
over  1912.  It  looks  rather  promising. 

Treating  carbon  as  any  other  element,  we  note  that 
it  combines  with  hydrogen  as  methane,  CH4,  or  marsh 
gas,  and  then  in  so  many  thousand  other  ways  that 
we  shall  drop  the  subject  for  the  present. 

With  oxygen  it  combines  to  CO,  leaving  two 
hooks  apparently  free.  Carbon  burned  with  insuffi- 
cient air  produces  this  gas.  It  is  very  poisonous  and 
burns  to  produce  CO2.  It  unites  directly  with  nickel 

230 


CARBON 

and  iron  to  Ni(CO)4  and  Fe(CO)5.  Owing  to  its 
tendency  to  unite  with  oxygen  to  form  CO2  at  a  high 
temperature,  it  is  a  good  reducing  agent — but  only  at 
high  temperatures. 

Carbon  dioxide,  CO2,  is  the  anhydrid  of  carbonic 
acid  and  is  known  as  carbonic-acid  gas.  It  is  very 
stable,  very  wide-spread,  and  its  salts  with  the  CO3 
radical  we  have  already  referred  to  many  times.  If 
CO2  is  the  anhydrid  of  the  acid,  then  CO2  -f  H2O  = 
H2CO3  would  indicate  the  real  carbonic  acid.  But,  as 
we  have  said  before,  we  cannot  separate  it  in  this  form; 
it  goes  right  over  to  H2O  and  CO2.  Nevertheless,  the 
salts  are  known.  It  is  a  very  weak  acid,  and  is  easily 
driven  off  by  a  stronger  one.  CO2  is  a  heavy  gas,  and 
may  be  poured  from  one  vessel  to  another  in  the  air. 
It  will  not  support  combustion,  and,  although  it  is  not 
poisonous,  it  will  not  support  life.  In  the  Dog's 
Grotto  (Grotta  del  Cane)  at  Naples,  where  CO2  comes 
from  the  earth,  it  remains  as  a  layer  on  the  ground 
while  the  wind  blows  the  upper  layers  of  it  away. 
If  a  man  and  a  dog  go  into  the  grotto,  the  man  passes 
through  at  his  ease  while  the  dog  suffocates. 

With  nitrogen  carbon  combines  (but  not  directly) 
to  cyanogen,  (CN)2.  This  C=N  is  a  gas.  Far  bet- 

C~N 

ter  known  is  prussic  acid,  HCN,  which  is  hydrogen 
cyanide,  the  most  poisonous  of  gases,  which  produces 
cyanides  of  metals  and  forms  innumerable  complex 
salts  in  organic  chemistry. 

Of  the  halogen  compounds  we  shall  mention  only 
carbon  tetrachloride,  CC14,  which  is  a  heavy  liquid, 
over  one  and  one-half  times  the  weight  of  water,  with 
a  pungent  chloroform-like  odor  and  an  anesthetic  ac- 
tion. It  is  used  as  a  solvent  and  for  extinguishing  fires. 
16  231 


EVERYMAN'S    CHEMISTRY 

Carbon  bisulphide,  CS2,  is  a  volatile,  highly  inflam- 
mable liquid  that  smells  like  a  good  old  orthodox  idea 
of  the  Judgment  Day.  It  is  used  to  destroy  insects,  as 
a  solvent  for  rubber  and  sulphur,  and  lately  it  has 
been  largely  used  in  the  manufacture  of  artificial  silk. 


PART   THIRD 
ORGANIC   CHEMISTRY 


XIX 

PARAFFINS  AND  PETROLEUM  BODIES 

Paraffins,  or  the  Fats — The  Carbon  Chains — Petroleum  Industry — 
The  Refiner's  Problems — Cracking — Oil-gas — Lubricants — The 
Future  of  Petroleum — List  of  Paraffins 

WE  told  in  the  first  chapter  about  the  manner  in 
which  one  carbon  atom  with  its  four  hooks 
will  connect  one  or  more  of  them  with  another  carbon 
atom,  leaving  the  free  hooks  to  connect  up  with  any- 
thing else  that  is  available.  We  may  represent  the  car- 
bon atom  with  its  four  hooks  as  — C —  and  the  sim- 

H 

I 

plest  hydrocarbon,  methane,  or  CH4,  as  H — C — H. 

H 

Now  let  us  take  another  body  of  the  same  methane 
or  paraffin  series,  called  butane,  or  C4Hi0,  and  we  meet 
a  new  problem.  The  arrangement  of  the  atoms  in  the 
molecule  may  be — 

HHHH  HHH 

itii  iii 

H-C-C-G-C-tf  or  H-G-6-C-H 

i  i  i  i  ill 

HHHH  n\H\ 

»¥• 

Bufane  Isobutane 

235 


EVERYMAN'S    CHEMISTRY 

and  these  bodies  differ  from  one  another.  These  are 
the  only  possible  arrangements  of  the  butane  mole- 
cule. Try  for  yourself  and  see.  The  next  body,  ac- 
cording to  the  number  of  carbon  atoms,  pentane, 
C5Hi2,  has  three  isomeric  possibilities,  but  when  we 
go  up  to,  say,  CiaH^s,  there  are  802  of  these  different 
hydrocarbons  possible.  We  shall  not  pursue  this  agony 
any  further  except  to  indicate  differences  in  fact  when 
there  is  no  difference  in  the  proportionate  number  of 
carbon,  hydrogen,  and  other  atoms  in  the  molecule. 
Two  or  more  bodies  having  the  same  chemical  content, 
but  differing  in  the  arrangement  of  their  molecules, 
are  called  isomers,  and  their  relation  to  one  another 
is  isomeric. 

This  means  that  molecules  are  real  things,  having 
shape  and  form  and  structure.  Just  as  two  different 
houses  may  be  built  of  the  same  number  and  kind 
of  brick  and  stone  and  yet  not  be  at  all  alike,  so  various 
molecules  may  be  constructed  of  the  same  number 
of  C,  H,  and  O  atoms  and  yet  be  entirely  different 
because  the  atoms  are  differently  placed  in  their  rela- 
tion to  one  another.  I  pray  you  do  not  let  this  arouse 
the  fear  that  you  will  not  understand  what  follows. 
The  subject  of  the  respective  places  held  by  atoms  in 
molecules  is  called  stereochemistry,  and  its  develop- 
ment is  one  of  the  great  works  of  Jacobus  Henricus 
van't  Hoff,  the  great  Dutch  physical  chemist;  but 
we  shall  not  enter  into  it.  I  mention  it  now  so  that 
we  may  point  out  certain  vistas  of  research  as  we  go 
along  in  considering  the  chemistry  of  living  things, 
which  is  in  effect  the  chemistry  of  that  remarkable 
element  carbon. 

Organic  compounds  are  generally  of  two  great 
groups.  The  first  includes  the  aliphatic  compounds, 
to  which  all  animal  and  vegetable  fats  belong.  The 

236 


PARAFFINS  AND  PETROLEUM  BODIES 

starting-point  is  methane,  CH4,  and  the  first  series 
is  the  paraffins,  which  we  shall  consider  immediately. 
The  second  group  embraces  the  aromatic  compounds, 
and  many  of  the  first  bodies  discovered  which  belong 
to  this  division  are  characterized  by  an  agreeable 
aroma.  The  name,  however,  is  misleading,  for  some 
dreadful  stenches  are  produced  by  so-called  "aro- 
matic" bodies.  The  unit  of  the  second  group  is  ben- 
zol, or  benzene,  C6H6,  which  we  shall  consider  later. 

PARAFFINS. — One  atom  of  carbon  will  combine  with 
four  atoms  of  hydrogen  and  make  a  stable,  satisfied 
compound,  indicated  by  CH4,  which  is  a  gas  and  is 
called  methane:  C==H4.  It  is  also  called  marsh  gas, 
because  if  you  stir  up  the  bottom  of  a  swamp,  bubbles 
of  this  gas  will  rise.  Natural  gas  is  composed  chiefly 
of  methane.  Now  let  us  take  the  next  in  order — two 
atoms  of  carbon  with  all  the  hydrogen  we  can  attach : 

C=H3 
I 

Ethane 

This  is  C2H6,  and  is  called  ethane. 
The  next  would  be 

y  t 

r^/y  C3H8,  or  propane,  and  the  next  is  4 


M  C4Hio,  or  butane. 

The  list  goes  up  to  C6oHi22,  and  higher. 

Now  let's  get  the  anatomy  of  these  molecules  clear 

0^*7 


EVERYMAN'S   CHEMISTRY 

in  our  minds.  They  are,  you  observe,  chains  of  car- 
bon atoms  connected  with  one  another  by  a  single  link 
or  bond,  three  hydrogen  atoms  at  each  end  and  two 
attached  to  each  intervening  carbon  atom.  There  are 
twice  as  many  hydrogen  atoms  as  there  are  of  carbon , 
and  then  two  more,  owing  to  the  extra  hydrogen  atom 
at  each  end.  They  are  composed  only  of  carbon  and 
hydrogen,  and  the  general  formula  is  CnH2n  +  2. 
These  hydrocarbons  are  known  as  paraffins. 

Of  course,  nature  has  what  appears  to  be  almost  a 
passion  to  mix  things  up,  and  so  crude  petroleum  has 
usually  a  great  many  other  bodies  besides  this  group ; 
it  contains  unsatisfied  hydrocarbons  called  olefins 
and  that  everlasting  sulphur  is  found  in  combination 
in  many  oils,  but  this  CnH2n  +  2  is  the  true  petroleum 
or  paraffin  group.  Observe  that  the  names  end  in 
ane,  and  after  the  first  four,  methane,  ethane,  propane, 
and  butane,  they  take  the  Greek  or  Latin  numeral 
corresponding  to  the  number  of  carbon  atoms.  Thus 
octane  is  C8Hi8,  dodecane  is  Ci2H26. 

As  the  number  of  atoms  in  the  molecule  increases, 
they  grow  heavier  and  they  develop  from  gases  to 
light  liquids,  over  to  heavy  oils,  and  finally  to  wax 
and  pitch.  This  is  natural;  with  a  great  mass  of 
atoms  in  the  molecule,  the  product  is  more  likely  to 
be  solid,  and  with  very  few  it  tends  to  be  gaseous. 
This  is  a  truth  with  so  many  exceptions  as  to  cast 
doubt  upon  it,  but  it  should  explain  why  CH4  can  be  a 
gas.  As  already  noted,  we  cannot  imagine  a  mole- 
cule of  carbon  to  contain  less  than  twelve  carbon 
atoms.  Diamond  and  graphite  both  surely  contain  a 
great  many  more.  CH4,  on  the  other  hand,  contains 
but  one,  connected  up  with  four  light  hydrogen  atoms. 
No  wonder  it  floats. 

Natural  gas  is  sometimes  stripped  of  its  heavier 

238 


PARAFFINS  AND  PETROLEUM  BODIES 

hydrocarbons,  which  may  be  used  for  gasolene,  while 
the  remaining  methane  is  sold  as  fuel  or  for  light. 
The  liquid  product  is  known  as  "casing  head"  or 
natural-gas  gasolene,  and  this  brings  a  very  good  price 
because  heavier  oils  may  be  mixed  with  it  and  the 
product  sold  as  gasolene. 

Crude  petroleums  are  exceedingly  variable  in  com- 
position, but  it  is  the  business  of  the  refiner  to  get 
similar  marketable  products  from  them.  Or,  rather, 
it  is  the  business  of  the  refiner  to  get  out  of  crude 
bodies,  oil  which  he  can  sell.  The  art  of  refining, 
which  consists,  in  effect,  in  separating  the  different 
groups  of  hydrocarbons  from  one  another  by  distilla- 
tion, is  full  of  difficult  problems  to  be  solved.  Mr. 
Refiner  has  his  crude  oil  as  the  raw  product,  and  with 
his  finished  products  he  must  meet  the  market. 
Formerly  the  great  demand  was  for  kerosene:  "water 
white,"  with  a  fire  test  of  150°  Fahrenheit  (65.5° 
centigrade),  and  "export  oil,"  with  a  fire  test  of  100° 
Fahrenheit  (43.3°  centigrade),  while  gasolene  was  a 
drug  on  the  market.  The  difference  between  these 
bodies  is  that  gasolene  is  composed  of  a  series  of  hy- 
drocarbons nearer  CH4,  while  kerosene  is  made  up  of 
a  higher  series,  nearer  the  lubricating  oils. 

Some  of  us  can  remember  when  kerosene  was  usu- 
ally dark  yellow  or  reddish  in  color,  and  that  lamp- 
wicks  used  to  grow  gummy.  This  is  now  avoided  by 
treating  the  refined  products  first  with  sulphuric  acid, 
which  drives  out  of  combination  the  tarry  bodies  and 
other  undesirable  products,  and  then  treating  with 
caustic  soda  takes  out  the  remainder  of  that  which  is 
not  wanted  and  also  neutralizes  the  sulphuric  acid. 

The  situation  formerly  was  that  the  refiner  could 
not  sell  his  gasolene,  and  some  of  us  may  remember 
that  efforts  were  made  by  the  refining  companies  to 

239 


EVERYMAN'S    CHEMISTRY 

develop  the  use  of  gasolene-stoves  and  the  unwilling- 
ness of  the  insurance  companies  to  insure  houses  and 
furniture  where  gasolene-stoves  were  used.  The  re- 
finers wanted  to  get  out  all  the  kerosene  and  lubri- 
cating oils  they  could,  and  as  little  gasolene.  Now 
the  tables  are  turned.  The  amount  of  oil  refined 
has  increased,  but  not  fast  enough  to  produce  enough 
gasolene  for  the  increasing  number  of  automobiles 
produced.  On  the  other  hand,  electricity,  coal-gas, 
and  acetylene  have  taken  the  place  of  kerosene-oil 
lamps,  and  what  with  the  war  closing  European  ports, 
the  refiners  cannot  sell  their  kerosene.  Even  more  of 
a  drug  is  the  " export  oil,"  a  kerosene  which  flashes 
at  a  lower  temperature  than  the  United  States  re- 
quirements. 

To  meet  the  increased  demand  for  gasolene,  refiners 
have  been  sorely  put  to  it.  There  was  not  enough, 
and  there  is  not  enough  to-day.  The  demand  is  in- 
sistent. The  usual  test  for  gasolene  is  to  measure  its 
specific  gravity — to  let  a  hydrometer  float  in  it.  This 
is  a  glass  bulb  with  a  long  graduated  stem,  and  the 
specific '  gravity  may  be  determined  by  reading  the 
figure  on  the  stem  at  the  surface  of  the  liquid  and  cor- 
recting the  figure  to  accord  with  the  temperature  and 
barometric  pressure.  The  lighter  the  liquid  the  deeper 
the  hydrometer  sinks,  and  vice  versa.  Now,  instead  of 
taking  what  they  call  a  "single  cut"  of  gasolene — that 
is,  the  gasolene  that  distils  over  at  the  required  tem- 
perature— they  take  heavier  oils  and  lighter  ones  and 
mix  them  together,  thus  giving  the  specific  gravity 
called  for,  but  containing  bodies  on  both  sides  of  gaso- 
lene as  it  were — heavier  and  lighter  bodies.  The 
chemical  structure  is  not  the  same.  Everything 
goes  as  gasolene  until  an  oil  is  reached  that  is  so 
heavy  that  it  will  carbonize  in  the  cylinders.  This  is 

240 


PARAFFINS  AND  PETROLEUM  BODIES 

not  trickiness  on  the  part  of  the  refiners;  it  is  grim 
necessity. 

The  heavier  the  petroleum  bodies  are  the  more 
likely  they  seem  to  be  to  go  over  into  their  elemental 
carbon  and  hydrogen  and  thus  produce  coke  in  the 
cylinders  rather  than  to  burn  to  water  and  carbon 
dioxide,  the  way  the  lighter  ones  do.  And  the  pres- 
ence of  the  heavy  oils  in  the  mixture  sold  as  gasolene 
is  a  contributing  factor  to  the  carbonization  of  oils  in 
cylinders,  but  it  is  not  the  sole  cause.  Some  users 
mix  gasolene  and  kerosene  half  and  half  for  automo- 
biles in  summer,  but  cranking  up  a  heavy  car  on  this 
mixture  in  winter  would  hardly  be  enjoyable. 

In  fact,  this  will  probably  be  the  next  step  in  auto- 
mobile fuel — a  starting  device  with  alcohol  or  gaso- 
lene, and  then  kerosene  for  the  trip.  The  tendency  of 
kerosene  to  leave  free  carbon  in  the  cylinders  after 
the  explosion  is  the  greatest  problem  to-day,  although 
the  number  of  trucks  using  kerosene  is  constantly  in- 
creasing. If  some  one  will  devise  an  improved  car- 
buretor, or  if  somebody  else  will  discover  an  efficient 
oxidizing  agent  to  mix  with  the  kerosene  so  that  it 
leaves  the  cylinders  clean,  the  problem  will  be  solved; 
but,  despite  all  sorts  of  claims,  nothing  satisfactory 
has  been  brought  out  yet.  It  is  likely  to  come  soon, 
but  whether  in  the  carburetor  or  in  the  kerosene 
oxidizing  agent  is  hard  to  tell. 

Cracking.  With  the  need  of  so  much  of  the  lighter 
oils,  the  art  of  " cracking"  petroleum  has  developed. 
This  means  just  what  it  says:  the  molecule  is  split, 
and  lighter  petroleum  hydrocarbons  are  cracked  off  of 
it.  From  the  residue  still  others  may  be  cracked  off, 
and  in  this  manner  the  output  of  light  hydrocarbons 
greatly  increased,  but  there  is  a  limit  to  this.  Cracking 
is  the  general  application  of  the  rule  that  organic  com- 

241 


EVERYMAN'S    CHEMISTRY 

pounds  are  decomposed  by  heat.  It  was  observed  in 
1855  that  petroleum  or  its  products  could  be  distilled 
at  other  temperatures  than  the  normal  boiling-points 
of  the  constituents.  What  happens  is,  as  we  have 
just  said,  that  parts  of  the  molecules  split  off  as  lighter 
hydrocarbons,  and  this  is  termed  "cracking."  It  is 
now  effected  by  distillation  under  pressure  or  by  de- 
composing the  oil  upon  a  highly  heated  surface.  A 
process  as  simple  as  this  would  seem  to  be  easy  of 
solution,  but  there  are  tricks  to  it:  in  the  first  place, 
very  heavy  oils  leave  a  residue  of  too  much  coke; 
some  Mexican  crudes,  on  ordinary  distillation,  will 
crack  and  leave  a  residue  of  40  per  cent.  coke.  Again, 
in  all  distillation  of  petroleums  some  cracking  takes 
place.  In  cracking  residues,  unless  the  pressure  is 
just  right,  the  result  is  unsatisfactory  because  instead 
of  paraffins  too  many  unsatisfied  hydrocarbons  are 
produced  which  are  shy  of  hydrogen  among  the  lighter 
bodies.  A  little  figuring  will  show  what  happens :  let's 
take  the  general  formula  CnH2n+2  and  say  n=3o. 
Then  we  should  have  C3oH62.  Now  if  we  were  to  split 
this  in  two  we  should  have  CisH^+CisHao,  and  with 
n  =  i5  we  should  have  for  the  second  body  CnEfon 
instead  of  CnH2n-f  2.  This  would  be  an  ill-smelling 
olefin.  They  do  no  harm,  but  they  do  not  smell  sweet. 
They  may  be  removed  by  treatment  with  sulphuric 
acid.  There  are  other  reasons,  however,  why  freshly 
cracked  gasolene  smells  badly,  which  are:  presence  of 
sulphur  compounds  and  traces  of  naphthenic  acids 
and  nitrogen  bases,  which  are  too  feeble  to  combine. 
Treatment  with  metallic  sodium  or  oxide  of  copper 
will  cause  the  evil  smells  to  disappear.  It  is  a  matter 
of  expense.  Generally  speaking,  the  higher  the  press- 
ure used  in  cracking  the  less  light  olefins  are  produced. 
W.  M.  Burton  was  the  first  to  develop  the  art  of 

242 


PARAFFINS  AND  PETROLEUM  BODIES 

successful  cracking,  and  now  over  3,000,000  barrels 
a  year  are  produced  by  his  process.  After  distilling 
off  the  gasolene  and  kerosene  contained  in  the  crude 
oil,  he  raises  the  boiling-point  by  back  pressure  upon 
liquid  and  vapors  to  75  pounds  per  square  inch  in 
an  especially  arranged  still. 

The  Rittman  process  consists  in  vaporizing  the 
petroleum  and  passing  it  into  hot  tubes,  450°  centi- 
grade, under  pressure  of  90  to  500  pounds  per  square 
inch,  according  to  the  nature  of  the  oil.  The  vapors 
are  condensed  under  pressure. 

An  interesting  chemical  process  which  is  not  a 
cracking,  but  which  has  the  same  application,  consists 
in  treating  the  oils  with  A1C13,  breaking  down  the  high 
boiling  oils  to  lower  ones.  A  number  of  patents  have 
been  issued  in  relation  to  this.  The  advantages  are 
that  very  little  gas  is  evolved  and  the  carbon  is  not 
deposited  as  hard  baked  on  the  bottom  of  the  still, 
but  as  a  granular  mass,  easily  removed.  The  low- 
boiling  oils  are  sweet-smelling,  water  white,  and  need 
no  further  refining. 

The  high-boiling  oils  are  refined  and  purified,  and 
come  into  use  as  lubricants,  while  still  higher  bodies 
are  used  for  fuels.  For  instance,  the  oil  that  comes 
over  after  kerosene  and  before  the  lubricating  oils  is 
known  as  gas-oil,  which  is  used  in  the  manufacture 
of  illuminating  gas  and  was  referred  to  under  the 
chapter  on  carbon.  This  gas-oil,  if  brought  to  a  high 
temperature,  in  an  apparatus  free  from  air,  decom- 
poses. One  of  the  products  of  the  decomposition  is 
called  oil-gas.  Now  this  oil-gas,  duly  liquefied  under 
pressure,  is,  in  substance,  Blaugas,  which  has  found 
considerable  domestic  use  in  some  localities.  Oil- 
gas  is  rich  in  ethylene,  which,  upon  treatment  with 
chlorine, yields  ethylene  dichloride,  C3H8C12.  The  chkh 

343 


EVERYMAN'S    CHEMISTRY 

rine  may  be  replaced  by  —  OH  groups,  whereby  ethy- 
lene  glycol,  a  glycerin  substitute,  is  obtained.  It  is 
predicted  that  this  compound  will  replace  glycerin  for 
many  purposes,  such  as  the  making  of  anti-freezing 
mixtures,  in  the  treatment  of  leather,  etc. 

Lubricating  oils  are  obtained  especially  from  the 
Appalachian  and  mid-continent  petroleums.  The 
most  important  of  these  lubricants  are  so-called  engine 
oil  and  cylinder  stocks.  The  story  of  lubricating  oils 
is  an  extremely  interesting  one,  but  too  rich  in  detail 
to  narrate  here.  Suffice  it  to  say  that  where  they  are 
obtained  they  constitute  the  most  valuable  products 
of  petroleum,  and  a  great  deal  of  skill  is  necessary  in 
refining  them.  They  range  from  common  engine  oils 
to  those  selling  for  several  hundred  dollars  a  gallon 
for  lubricating  watches. 

THE   FUTURE    OF   PETROLEUM 

Neither  petroleum  nor  natural  gas  will  last  forever, 
especially  when  we  consider  the  lavish  way  in  which 
we  are  using  up  these  natural  products.  But  new  uses 
loom  up  that  are  promising  even  if  the  present  uses 
should  be  discontinued  on  account  of  cost.  For  in- 
stance, when  the  supply  of  natural  gas  wanes  so  that 
it  is  not  economical  to  sell  it  for,  say,  less  than  fifty 
cents  per  1,000  cubic  feet,  it  will  come  into  compe- 
tition with  power  generated  by  gas-engines  fed  by  by- 
product coke-oven  gas.  Then  there  can  develop  as 
distinct  a  natural-gas  industry  as  that  of  coal-tar. 
For  natural  gas  contains  from  85  to  95  per  cent,  of 
methane,  CH4,  the  starting-point  of  the  half  of  organic 
chemistry.  Now  let  us  imagine  this  chlorinated  to 
carbon  tetrachloride,  CC14.  Here  is  a  solvent  that 
needs  only  to  be  Droduced  in  this  manner  to  find  very 

244 


PARAFFINS  AND  PETROLEUM  BODIES 

wide-spread  use.  The  same  may  be  said  of  chloroform, 
CHC13,  and  of  dichlormethane,  CH2C12,  which  is  a  bet- 
ter anesthetic  than  chloroform,  and  may  also  be  used  as 
a  solvent.  Methyl  chloride,  CH3C1,  is  a  gas  that  will 
have  wide  application  as  a  refrigerating  agent;  it 
boils  at  — 15°  centigrade.  These  are  industries  not 
yet  developed.  Again,  by  oxidation,  the  methane 
may  be  used  in  the  production  of  formic  and  oxalic 
acids,  and  to  make  formaldehyde  and  methyl  or  wood 
alcohol.  In  petroleum  there  are  seldom  found  free 
fatty  acids,  but  the  fatty  hydrocarbons  are  there. 
By  treatment  with  chlorine  and  magnesium  and  CO2 
through  a  series  of  processes  that  we  shall  not  study 
out,  and  by  further  treatment  with  sulphuric  acid  and 
water,  the  fatty  acids  are  liberated,  although  the  cost 
of  these  acids  is  still  too  high.  But  certain  of  these 
acids  may  be  converted  into  glycerides,  which  mean 
real  fats,  and  so,  as  soon  as  the  processes  are  perfected, 
edible  fats  may  be  made  from  petroleum.  Another 
subject  that  has  already  received  attention  is  the  rela- 
tion of  petroleum  to  the  manufacture  of  soap.  That 
would  come  from  the  artificial  fatty  acids  produced. 

Here  is  a  list  of  some  of  the  paraffin  bodies  with  their 
melting-points  and  observed  boiling-points.  Note 
how  the  names  after  butane  indicate  in  Latin  or 
Greek  the  number  of  carbon  atoms  and  how,  as  they 
increase  in  the  number  of  atoms  in  the  molecule,  they 
are  progressively  liquids  and  then  solids.  This  is 
shown  in  the  melting-points  and  boiling-points. 

Observed 
Formula  Name  Melting-point  Boiling-point 

CH4  Methane  -i860C.  -i6o0C. 

C2H6  Ethane  —172  —  93 

C3H8  Propane  —  45 

Butane  I 

245 


EVERYMAN'S  CHEMISTRY 

Observed 

Formula                   Name  Melting-point  Boiling-point 

C6Hi2                Pentane  ........  36.40. 

CeHi4                Hexane  ........  68  .  9 

C7Hi6                Heptane  ........  98  .  4 

C8Hi8                Octane  ........  125  .  6 

C9H20                Nonane  —  5iC.  149-5 

CioHzz               Decane  -  31  173 

CnH24               Undecane  —  26  194 

C12H26               Dodecane  —  12  214 

Ci4H3o               Tetradecane  4  252 

Ci6H34               Hexadecane  18  287 

C20H42               Eicosane  36.5  205 

C23H48               Tricosane  47.4  234 

C36H72               Pentatriacontane  74  331 

Hexacontane  101  ........ 


Boiling-points  of  eicosane,  tricosane,  and  pentatri- 
acontane  were  observed  at  15  mm.  pressure  instead 
of  at  that  of  the  atmosphere,  which  accounts  for  the 
difference. 


XX 

OLEFINS   AND    ACIDS 

Olefins  —  What  Unsatisfied  Means  in  Organic  Chemistry  —  A  Little 
Sermon  on  Possibilities  with  Acetylene  as  a  Text  —  Harmless 
Moving-Picture  Films  —  Fatty  Acids  —  Unsaturated  or  Unsatis- 
fied Acids 


OING  back  to  the  paraffin  bodies  and  bearing  in 
mind  that  they  are  methane,  CKU;  ethane,  C2He", 
with  the  general  formula  CnH2n-f2,  the  olefins,  as 
they  are  called,  have  the  formula  CnH2n,  or  two  atoms 
less  of  hydrogen.  The  termination  "ylene"  is  added 
to  the  type  prefix,  so  that  methylene  would  be  CH2  and 
ethylene  C2H4.  They  are  not  very  stable.  Methylene 
is  not  known  in  a  free  state  and  ethylene  is  a  sweetish- 
smelling  gas  which  combines  readily  with  other 
bodies.  Ethylene  chloride,  for  instance,  is  C2H4Cl2. 
You  observe  that  the  halogen  adds  itself  on  without 
replacing  any  hydrogen  atoms  in  the  molecule.  They 
are  formed  in  the  dry  distillation  of  complicated  car- 
bon compounds,  which  accounts  for  the  presence  of 
four  to  five  per  cent,  of  them  in  coal-gas.  They 
are  also  produced  by  the  elimination  of  the  elements 
of  water  from  alcohols  and  by  other  means  as 
well.  The  lower  members  are  gases;  then,  as  the 
molecules  increase  in  the  number  of  atoms,  they  are 
liquids;  and  finally  the  highest  members  are  solids. 
These  unsaturated  hydrocarbons,  as  they  are  called, 
are  unsaturated  because  there  are  one  or  more  carbon 
17  247 


EVERYMAN'S    CHEMISTRY 

bonds  that  are  free  or  because  the  carbon  atoms  are 
hooked  together  by  more  than  one  bond  or  because 
carbon  under  certain  circumstances  has  only  two  or 
three  bonds — which  looks  like  a  fact,  but  is  too  trouble- 
some for  us  to  consider.  The  lower  members  of  this 
CnH2n  group  are  generally  unstable,  whereas  the 
higher  members  are  stable. 

Another  series  of  unsaturated  hydrocarbons  have 
the  general  formula  CnH2n  — 2,  which  indicates  that 
the  carbon  atoms  are  united  by  a  triple  bond,  as  in 
acetylene,  C2H2  or  H  —  C=C  — H.  The  second  of  this 
group,  C3H4,  is  called  allylene,  and  the  higher  numbers 
are  referred  to  as  substituted  acetylenes,  as  C4H6, 
ethylacetylene;  C6Hi0,  butylacetylene,  etc.  The  most 
important  is  acetylene,  C2H2,  or  C — H 

III 
C— H 

It  is  a  gas  that  is  full  of,  tricks.  Air  mixed  with  from 
3  up  to  82  per  cent,  of  acetylene  will  explode.  The 
explosive  limits  of  air  with  coal-gas  are  only  from 
5  to  28  per  cent.  Those  three  bonds  that  are  engaged 
in  holding  together  the  two  carbon  atoms  are  not 
very  closely  engaged.  Their  job  is  hardly  enough  for 
all  three  of  them  to  keep  them  busy;  and  if  anything 
available  to  combine  with  is  around,  they  are  likely 
to  find  it.  That  is  where  the  danger  from  impurities 
in  acetylene  comes  in.  Let  us  indicate  just  one  more 
unsaturated  group  in  which  there  appear  two  double 
bonds  between  carbon  atoms,  like  this: 

\       y  u 

'/C-C-cCyy   or  C5H8,  known  as  isoprene. 

if 

Isoprene] 

By  the  union  of  two  or  more  molecules  it  passes  over 

248 


OLEFINS 

with  terpenes,  Ci0Hi6,  into  rubber.    This,  then,  is  the 
road  to  synthetic  rubber. 

Acetylene,  you  may  recall,  is  produced  by  the  action 
of  water  upon  calcium  carbide  : 


CaC2  +  2H2O  =  CaHa  +  Ca(OH)2 
calcium  water  acetylene  slacked 
carbide  lime 

c 

Now  this  triple  bond  between  the  two  carbon  atoms, 

C—  H 

HI          and  the  fact  that  we  have  two  atoms  of  car- 

C—  H 

bon  linked  together,  makes  acetylene  an  interesting 
starting-point  for  the  production  of  many  organic 
bodies,  and  whole  vistas  have  been  opened  up  as  a 
result  of  research  during  the  past  few  years.  At  the 
risk  of  making  acetylene  appear  of  more  general  im- 
portance than  it  is,  let  us  consider  some  of  the  things 
that  may  be  done  with  it.  It  will  serve  as  a  good  ex- 
ample of  the  adventures  to  be  met  in  research  in  or- 
ganic chemistry.  In  other  words,  we  started  with  lime 
and  coke  to  make  calcium  carbide  and  by  adding  water 
we  obtained  acetylene.  Now  let  us  observe  whither 
we  are  led  from  these  modest  beginnings,  from  lime 
and  coke  at  the  start. 

Acetylene  burns  with  a  very  luminous  flame  and 
is  used  for  domestic  lighting.  When  the  carbide 
process  was  first  introduced  it  was  thought  that  this 
would  be  its  chief  use,  but,  while  it  has  not  achieved 
the  popularity  that  was  expected  of  it,  the  uses  of 
acetylene  and  calcium  carbide  have  increased  in  other 
directions,  while  the  possibilities  are  illuminating  as 
showing  how  unexpected  the  workings  of  organic 
chemistry  are. 

A  flame  of  acetylene  burned  with  oxygen  is  so  hot 

249 


EVERYMAN'S    CHEMISTRY 

that  it  will  cut  through  several  inches  of  iron  or  steel. 
The  street-railway  repair  gangs  are  often  seen  using 
this,  and  it  is  interesting  to  watch  them  cutting 
through  rails  or  welding  them  with  the  infernally  hot 
oxyacetylene  flame.  It  is  so  bright  that  it  is  dan- 
gerous to  look  at  for  any  length  of  time,  and  the  men 
need  to  use  darkened  spectacles  to  preserve  their  sight 
when  they  work  with  it. 

Acetylene  gas  is  compressed  in  cylinders  by  absorp- 
tion in  acetone  and  used  for  lighting  buoys  at  sea, 
and  in  rivers  and  harbors.  There  are  many  thousand 
such  buoys  in  use  in  the  United  States  service.  They 
are  little  lighthouses  that  keep  going  day  and  night 
for  weeks  at  a  time  and  need  no  keeper. 

Another  gas  of  the  petroleum  series,  ethane,  C2H4, 
may  be  produced  by  bringing  hydrogen  together  with 
acetylene  in  the  presence  of  certain  metals  that  act 
as  catalysts,  or  chemical  parsons,  and  perform  the 
marriage  of  hydrogen  to  acetylene,  so  that  ethane 
results.  There  does  not  seem  to  be  much  call  for 
ethane  at  present  for  chemical  work,  but  you  never 
can  tell  how  soon  somebody  may  want  it  in  the  worst 
way. 

Now  let  us  consider  a  certain  German  works  in 
operation  before  the  war.  Acetylene  gas  under  six  to 
ten  atmospheres'  pressure  (90  to  150  pounds  to  the 
square  inch)  was  led  into  strong  steel  cylinders  and 
an  electric  spark  was  passed  through  it.  Back  the 
whole  thing  went  to  its  elemental  parts  of  carbon  and 
hydrogen.  But  this  carbon  was  in  the  form  of  such  a 
fine,  pure  soot  that  it  was  sold  at  handsome  prices  in 
China  and  Japan  and  to  European  paint  manufactur- 
ers for  lacquers  and  black  varnishes. 

In  two  other  establishments,  by  more  work  with  a 
catalyst  (ancl  this  time  antimony  did  the  business), 

250 


OLEFINS 

they  produced  combinations  with  chlorine,  and  by 
that  kind  of  chemical  chicanery,  which  is  almost  more 
of  an  art  than  a  science,  a  whole  series  of  ethylene 
chlorides  have  been  produced  that  are  remarkable 
solvents.  They  are  almost  indifferent  to  metals 
(which  means  that  they  do  not  injure  their  containers) ; 
they  are  inactive  toward  acids  and  alkalies,  and  they 
do  not  burn  easily.  They  are  useful  in  the  varnish, 
soap,  and  many  other  industries;  they  point  to  the 
possibility  of  scientific  laundries  in  which  clothes  may 
be  washed  without  injury,  and  their  wide-spread  use  is 
only  a  matter  of  cost.  Another  of  them,  ethylene  per- 
chloride,  is  a  solvent  for  sulphur.  Then  if  we  start 
with  another  of  them,  ethylene  trichloride,  and  do 
various  things  to  it,  according  to  a  Nuremberg  patent, 
the  result  is — indigo !  Ethylene  chloride  is  said  to  be 
used  to  extract  the  caffeine  from  coffee  in  the  Kaffee 
Hag  works. 

Beginning  once  more  with  acetylene  gas  and  work- 
ing water  into  the  molecule,  we  have  the  aldehyde  of 
acetic  acid  or  acet aldehyde,  and  this,  on  oxidation, 
yields  acetic  acid.  Here  we  have  not  only  vinegar, 
but  an  acid  greatly  needed  in  chemical  manufacture. 
If  this  were  only  cheap  enough  we  should  have  incom- 
bustible celluloid  and  moving-picture  films.  Strangely 
enough,  the  weak  acetic  acid  will  combine  with  cellu- 
lose in  the  place  of  nitric  acid,  so  that  in  the  place  of 
nitrocellulose  or  guncotton  we  can  have  acetylcellu- 
lose,  which  is  reported  to  be  entirely  harmless.  It  is 
only  a  matter  of  cost.  As  soon  as  acetic  acid  is  cheap 
enough  the  unburnable  celluloid  industry  may  pro- 
gress. The  acet  aldehyde  is  further  interesting  in  that 
by  chemical  strategy  it  is  easy  to  make  it  polymerize, 
as  the  expression  is,  which  means  that  its  molecules 
may  be  bunched  together  into  new  combinations,  and 

251 


EVERYMAN'S    CHEMISTRY 

out  of  this  the  problem  to  make  fatty  acids  is  not 
difficult.  Just  how  expensive  it  would  be  to  make  the 
higher  fatty  acids  is  somewhat  of  a  guess;  but  from 
the  appearance  of  things  and  the  experience  of  men  of 
research,  it  should  not  be  very  great,  once  the  method 
is  worked  out. 

Glycerin  was  made  synthetically  by  Professor  Friedel 
in  Paris  many  years  ago,  but  since  then  no  one  has 
succeeded  in  doing  it,  to  my  knowledge.  It  should 
be  easy,  but  it  isn't.  When  you  think  you  have  got 
it,  you  haven't  got  it  at  all.  But  you  never  can  tell; 
really,  you  never  can  tell.  Some  day  before  long 
somebody  is  likely  to  solve  it;  and  glycerin  in  simple 
combination  with  the  higher  fatty  acids  is  lard,  tallow, 
shortening,  fat — what  they  are  crying  for  in  Germany. 
This  is  very  likely  to  come  some  day,  and  the  time 
may  not  be  distant  when  we  shall  have  good,  pure, 
edible  fats  made  from  coke  and  lime  as  the  starting- 
point. 

Now  if  we  reduce  this  aldehyde,  behold  alcohol  of 
the  old  John  Barleycorn  type!  But  if,  instead  of 
doing  these  things,  we  condense  acetylene  under  cer- 
tain conditions,  there  results  the  whole  string  of  coal- 
tar  bodies — benzene,  toluene,  naphthalene,  and  the  rest. 

Again,  starting  with  acetylene,  if  we  mix  it  with 
ethylene,  according  to  an  Austrian  patent,  and  then 
condense,  chlorinate,  and  do  other  things  to  it,  we 
finally  get  isoprene.  And  isoprene,  on  condensation, 
yields,  as  we  have  observed,  rubber,  synthetic  rubber, 
the  real  gum.  Butadiene,  a  first  cousin  to  isoprene, 
is  easy  to  make  from  acetylene,  and  the  economical 
production  of  isoprene,  which  is  most  of  the  way  to 
synthetic  rubber,  may  come  along  any  day. 

Some  of  these  processes  are  practical  and  some  are 
not.  Just  now,  neither  indigo  nor  rubber  may  be 

252 


OLEFINS 

profitably  obtained  from  this  source.  Acetic  acid,  on 
the  other  hand,  is  made  to-day  in  Canada  in  very  large 
quantities  from  acetylene  gas — pure,  glacial  acetic 
acid,  in  competition  with  that  made  from  the  acetate 
of  lime  of  the  wood  distillers — and  from  the  acetic 
acid  they  are  producing  acetone,  which  is  greatly 
needed,  among  other  things,  for  producing  cordite  for 
the  British  navy. 

Fatty  Acids.  Let  us  go  back  to  the  paraffin  bodies 
and  negotiate  a  molecule  of  carbon  dioxide  into  each  of 
them.  Then  we  shall  have  the  fatty  acid  of  the  next 
higher  body  of  the  series,  with  the  general  formula 
CnH2nO2.  This  may  not  be  very  clear,  and  it  is  not 
true  in  regard  to  the  first  of  the  series,  but  I  think  the 
idea  will  show  itself  in  a  minute.  They  are  also  pro- 
duced by  the  oxidation  of  alcohols,  but,  as  we  have 
not  come  to  alcohols  yet,  we  can  merely  record  it  as  a 
fact  and  wait  awhile  for  the  theory  of  it.  Note, 
please,  one  other  thing  about  organic  acids,  which 
is  that  they  contain  the  group  COOH,  or  what  is 

O 

II 
known  as  the  carboxyl  radical,  —  C— O— H. 

In  the  mean  time  let  us  consider  the  first  of  the 
series,  or  formic  acid,  CH2O2,  or,  to  get  it  clearer, 
HCOOH.  It  is  called  from  the  Latin  formica,  which 
means  ant,  and  it  is,  really,  the  unpleasant  acid  stuff 
that  some  ants  exude  in  defense.  It  is  an  important 
acid  as  we  shall  see  when  we  come  to  formaldehyde. 

Of  course,  these  acids  are  not  produced  by  bubbling 
carbon  dioxide  (CO2)  through  gasolene,  for  instance, 
because  the  catalyst  to  turn  the  trick  has  not  been 
discovered.  But  if  we  take  marsh  gas  or  methane, 
CH4,  and  add  to  it,  by  chemical  chicanery,  CO2,  we 
have  a  body  set  forth  as  C2H4O2,  and  that  is 

253 


EVERYMAN'S    CHEMISTRY 

Acetic  Acid.  Here  you  observe  the  CO2  wriggled 
into  CH4.  This  acid  has  been  known  longer  than  any 
other  and  is  obtained  by  the  oxidation  of  dilute  alcohol 
by  exposure  to  the  air,  besides  the  method  described 
under  acetylene.  Cider,  wine,  beer,  etc.,  turn  sour 
on  being  left  in  the  air,  and  that  sour  vinegar  is  acetic 
acid.  This  is  aided  by  acetic-acid  bacteria,  called 
"mother"  of  vinegar.  The  absorption  of  O  takes 
place  only  at  the  surface,  and  the  process  is  slow.  A 
solution  of  6  to  10  per  cent,  acetic  acid  is  obtained 
after  several  weeks.  In  the  quick-vinegar  process  a 
solution  of  10  per  cent,  alcohol  is  allowed  to  trickle 
over  beechwood  shavings  in  large  vats  through  which 
the  air  circulates.  The  shavings  are  first  drenched  in 
old  vinegar  so  as  to  provide  some  of  the  mother.  This 
is  a  ten-day  process,  and  the  product  contains  4  to  6 
per  cent,  of  acetic  acid.  It  is  also  obtained  by  the  dis- 
tillation of  wood.  The  distillate  contains  about  10  per 
cent,  of  acetic  acid,  which  is  caught  by  treatment  with 
quicklime,  so  that  acetate  of  lime  is  produced.  This 
is  again  treated  with  HC1,  which  drives  off  the  acetic 
acid,  which  is  distilled  over.  It  has  very  wide-spread 
use  in  the  industries,  and  certain  of  its  compounds  are 
especially  good  as  solvents  for  organic  bodies.  Pure 
acetic  acid  is  a  solid,  crystalline  substance  which  melts 
at  1 6. 6°  (about  60°  Fahrenheit),  but  the  addition  of 
very  little  water  makes  it  liquid. 

The  next  in  order  is 

Propionic  Acid,  C2H6COOH,  or  C3H6O2,  which  we 
do  not  come  across  very  often.  Then  follows 

Butyric  Acid,  C3H7COOH,  or  C4H802,  which  we 
occasionally  know  to  our  grief.  It  is  the  acid  of  rancid 
butter.  It  is  stable  and  is  occasionally  availed  of  in 
organic  research.  When  a  chemist  is  compelled  to 
work  with  it  in  the  laboratory  for  any  extended  time 

254 


OLEFINS 


his  availability  as  a  society  man  and  dinner  guest  is 
likely  to  wane.  It  is  a  smell  that  sticks  closer  than  a 
brother,  and  it  scorns  washing  and  rival  perfumes. 
There  are,  however,  some  other  compounds  in  which 
sulphur  has  taken  the  place  of  oxygen  in  alcohols, 
known  as  mercaptans,  that  can  beat  it.  So  can  a 
number  of  others.  In  an  atmosphere  in  which  methyl 
or  ethyl  mercaptan  abounds,  the  odor  of  butyric  acid 
almost  seems  like  precious  ointment. 

As  we  go  up  in  the  scale  of  these  fatty  acids  we  meet 
palmitic,  margaric,  stearic,  and  the  higher  acids, 
which,  attached  to  glycerin  as  a  base,  constitute  the 
salts  or  esters  which  are  animal  and  vegetable  fats 
and  oils.  Hence  the  name  fatty  acids.  We  shall 
observe  something  of  their  ways  when  we  come  to 
discuss  oils.  The  easy  rule  that  the  more  atoms 
there  are  in  the  molecule  the  more  solid  the  product 
does  not  seem  to  hold  good  with  fatty  acids.  Pure 
acetic  acid  is  a  solid  at  ordinary  temperatures,  and 
very  much  higher  ones  are  gases. 

Here  is  a  list  of  some  fatty  acids.  They  may  come 
in  handy  for  reference  some  time. 


Melts  at 


Found  in 

Red  ants. 

Some  fruit  juices, 
especially  vinegar. 

Rancid  butter. 

Valerian  wood. 

Rancid  cocoanut  oil. 

As  salts  (esters)  of 
animal  and  vege- 
table oils  and  fats. 


Unsaturated  Acids: 

Oleic  Acid  Series.    Just  for  record,  and  because  we 
shall  have  to  refer  to  them  again,  let  us  note  that 

255 


Name 

Formula 

C. 

Formic  acid 

H.C.O.OH 

3° 

Acetic  acid 

CH3COOH 

16.6 

Propionic  acid 

QHsCOOH 

-36 

Butyric  acid 

C3H7COOH 

—  2 

Valeric  acid 

C4H9COOH 

-58-5 

Caprionic  acid 

CfiHnCOOH 

-   i-5 

Palmitic  acid 

C15H3iCOOH 

62.6 

Margaric  acid 

C16H33COOH 

60 

Stearic  acid 

C17H33COOH 

69 

EVERYMAN'S    CHEMISTRY 

these  acids  contain  two  atoms  of  hydrogen  less  than 
the  fatty  acids.  Note  the  difference  in  two  of  them: 

Propionic  Acid  (fat  group)  is  C2H5COOH.  Acrylic 
Acid  (oil  group)  is  C2H3COOH. 

Stearic  Acid  (fat  group)  is  C17H35COOH.  Oleic 
Acid  (oil  group)  is  Ci7H33COOH. 

These  higher  acids  with  glycerin  as  a  base  are  the 
substance  of  many  oils.  But  nature  does  not  work 
according  to  military  rules;  the  stearates,  for  instance, 
are  not  all  lined  up  in  fats  and  the  oleates  in  oils.  On 
the  contrary,  this  base,  glycerin,  which  we  shall  soon 
have  to  deal  with,  has  three  available  bonds,  or  OH 
tails,  and  it  does  not  mind  at  all  having  that  number 
of  different  acids  attached  to  it.  The  oleic  group  is 
found  in  fats  and  the  fatty  group  in  oils;  all  we  can 
say  is  that  they  do  not  predominate.  The  rule  is  that 
fatty  acids  predominate  in  fats  and  oleic  acids  pre- 
dominate in  oils. 

Oxalic  Acid,  C2H2O4. 

This  belongs  to  a  group  having  two  COOH  radicals 
and  is  the  only  one  we  shall  note.  Its  formula  is 
COOH. COOH,  and  it  is  prepared  by  fusing  caustic 
soda  and  caustic  potash  with  sawdust.  This  produces 
first  a  formate,  which  on  further  heating  loses  hydro- 
gen and  doubles  up  to  oxalic  acid,  or  rather,  to  the 
oxalate.  Observe,  please,  how  formic  acid  goes  over 
into  oxalic : 

KOOC 

I 

2KOOCH     =     KOOC     +     H2 
formate  of         oxalate  of      hydro- 
potash  potash  gen 

Again,  oxalic  acid  may  be  switched  over  to  formic. 
Oxalic  acid  is  very  poisonous,  although  it  is  often  mixed 
with  abrasives  for  cleaning  brass  and  copper  orna- 

256 


OLEFINS 

ments,  because  it  is  not  so  corrosive  as  mineral  acids. 
The  other  acids,  malonic,  succinic,  etc.,  of  this  series 
we  shall  not  consider,  except  to  note  that  the  longer 
the  carbon  chain  in  the  molecule  the  weaker  the 
acid. 


XXI 


ALCOHOLS    AND    SOME    RELATIVES 

Alcohols — List  of  Many  Alcohols — John  Barleycorn  and  the  Drinks 
That  Contain  Him — Industrial  Alcohol — Its  Great  Value — Glyc- 
erin— Esters  and  Ethers — Aldehydes  and  Ketones,  More  Espe- 
cially Acetone — Halogen  Compounds 

JET'S  go  back  to  our  original  paraffins  again  and 
"  note  that  if  we  take  out  one  hydrogen  atom  and 
substitute  an  OH — that  is,  an  oxygen  atom  connected 
to  a  hydrogen  atom  in  the  place  of  it,  we  shall  get 
the  corresponding  alcohol.  Here  is  a  table  of  a  few 
of  them: 


Paraffin 

Formula 

Alcohol 

Formula 

Spec.  Gr. 

Boiling- 
point 

c. 

Methane 

CH4 

Methyl,  or  wood 

CH3OH 

.812 

660 

Ethane 

C2Hfl 

Ethyl,  or  grain 

C2H5OH 

.806 

78 

Propane 

C3H< 

Propyl 

C3H7OH 

.817 

97 

Butane 

C^io 

Butyl 

C4H9OH 

.823 

117 

Pentane 

C6H12 

Amyl,  or  fruit 

C,HiiOH 

.829 

137 

oil 

Hexane 

CeH14 

Hexyl 

C6H13OH 

•833 

157 

Heptane 

C7Hi6 

Heptyl 

C7Hi6OH 

.836 

175 

Octane 

CsHie 

Octyl 

C8H17OH 

•839 

191 

Nonane 

CsH20 

Nonyl 

C9H19OH 

.842 

213 

The  lowest,  methyl  or  wood  alcohol,  is  a  very  light 
liquid;  the  next,  grain  alcohol,  is  too  familiar  to  need 
description.  The  higher  bodies  are  oily,  and  as  they  go 
up  the  scale  they  become  solid.  By  shifting  that  OH 
group  around  to  different  parts  of  the  molecule  we 
can  get  an  increasing  number  of  isomeric  alcohols — 

258 


ALCOHOLS  AND    SOME    RELATIVES 

that  is,  the  same  in  content,  but  the  atoms  differently 
arranged  in  the  molecule.  We  shall  not  consider 
them.  Alcohols  with  five  to  eleven  atoms  of  carbon 
are  oily,  and  those  containing  more  than  twelve  atoms 
of  carbon  are  solid. 

Methyl  alcohol  is  obtained  by  the  dry  distillation 
of  wood,  keeping  the  air  from  reaching  it.  Three 
products  are  obtained — gases,  an  aqueous  liquid,  and 
tar.  The  liquid  contains  >£  per  cent,  of  methyl 
alcohol,  10  per  cent,  of  acetic  acid,  and  >£  per  cent,  of 
acetone,  more  or  less.  The  chief  use  of  methyl  alcohol 
is  in  the  coal-tar  color  industries,  as  a  solvent  for  gums 
and  varnishes,  to  denature  grain  alcohol  so  that  it  may 
not  be  drunk,  and  in  the  production  of  formaldehyde. 

Ethyl  alcohol  is  old  John  Barleycorn.  It  is  produced 
by  the  breaking  down  of  sugar  by  means  of  a  ferment 
known  as  yeast.  We  can  take  up  the  theory  of  this 
better  later  on,  when  we  have  considered  sugars. 
The  greatest  use  for  alcohol  still  is  for  drinking,  al- 
though it  is  of  enormous  value  in  industry  as  a  solvent, 
in  the  production  of  varnishes,  etc.,  in  the  preparation 
of  organic  bodies  of  all  sorts,  and  as  a  disinfectant  and 
preservative.  It  is  said  that  every  shell  shot  from  a 
1 2 -inch  gun  represents  one  barrel  of  alcohol  used  in 
the  manufacture  of  the  powder  to  fire  it.  It  ranks  very 
high  as  a  disinfectant.  The  following  are  the  principal 
beverages  and  their  alcohol  content: 

Beer.  Three  to  5  per  cent,  alcohol.  Made  by 
fermentation  of  malt,  which  is  barley  that  has  been 
allowed  to  sprout  and  then  heated  to  change  the 
starch  it  contains  to  diastase.  The  beer  family  of 
yeast  grows  on  the  bottom  of  the  vat  and  proceeds  to 
split  the  sugar  into  alcohol,  C2H5OH,  and  carbon  di- 
oxide, CO2.  Hops  are  added  to  give  flavor  and  to  add 
to  its  keeping  qualities.  Very  dark  beer  is  made  with 

259 


EVERYMAN'S    CHEMISTRY 

burnt  malt,  and  beer  of  the  Munich  type  is  made  of 
pure  malt  and  hops,  while  light  beers  are  made  of  a 
mixture  of  malt  and  rice  or  malt  and  corn  or  a  prepa- 
ration of  corn.  Pilsener  is  malt  and  rice — of  course, 
with  hops  added.  Cheaper  beers  are  made  by  substi- 
tutes, a  great  deal  of  corn  for  malt  and  producing  the 
dark  color  by  burnt  sugar,  which  is  caramel. 

Ale  contains  from  3  to  8  per  cent,  of  alcohol,  and 
some  stock  ales  contain  more.  The  ingredients  of  ale 
are  the  same  as  beer,  but  the  family  of  yeast  is  a  dif- 
ferent one,  and  the  process  is  not  the  same.  In  ale, 
the  yeast  grows  on  the  top  of  the  brewing-vat  and  the 
brewing  process  is  carried  on  at  ordinary  temperature 
instead  of  at  a  low  one. 

Wines  are  made  by  fermentation  of  the  sugar  in 
grapes.  The  alcohol  content  in  dry  wines  is  7  to  12  per 
cent.  Sweet  wines,  such  as  port,  sherry,  and  madeira, 
contain  15  to  20  per  cent,  alcohol,  but  to  produce  this 
strength  it  is  necessary  to  add  alcohol  because  the 
yeast  plants  are  killed  when  the  alcohol  content  of 
fermenting  wines  reaches  17  per  cent. 

Champagne  is  fermented  in  the  bottle  and  contains 
8  to  12  per  cent,  alcohol. 

Whisky  contains  25  to  45  per  cent,  of  alcohol,  and 
is  made  of  anything  that  contains  sugar,  but  chiefly 
from  corn  (Bourbon),  rye,  and  barley  malt,  and  some- 
times potatoes.  The  distiller  first  makes  a  beer  and 
then  distils  over  the  alcohol.  The  "proof"  of  whisky 
is  its  alcohol  content:  100  proof  is  50  per  cent.;  90 
proof  is  45  per  cent,  of  alcohol,  etc. 

Brandy,  with  40  to  50  per  cent,  of  alcohol,  is  made 
by  distilling  wine. 

Gin  is  grain  liquor  flavored  with  juniper  berries  and 
other  extracts. 

Rum  is  made  by  distilling  fermented  molasses. 

260 


ALCOHOLS   AND   SOME   RELATIVES 

The  experienced  rectifier  can  make  a  great  many 
kinds  of  wines  and  liquors  with  alcohol,  water,  sugar, 
and  some  flavoring  extracts,  although  the  wine- 
growers of  America  and  the  pure-food  laws  have 
brought  about  a  better  condition  of  alcoholic  drinks 
than  formerly  obtained  in  this  country.  A  vicious 
adulterant  of  whisky  that  was  formerly  sold  by  un- 
scrupulous dealers  was  methyl  or  wood  alcohol.  It 
is  claimed  that  if  methyl  alcohol  be  chemically  pure  it 
is  no  more  poisonous  than  ethyl  alcohol,  but  it  is 
rarely  made  pure.  The  commercial  product  contains 
acetone  and  other  impurities,  and  it  is  such  a  mean 
poison  that  many  victims  who  survive  a  grand  drunk 
on  it  lose  their  sight.  Those  whom  it  does  not 
kill  it  is  likely  to  blind,  as  it  has  a  destructive  effect 
upon  the  optic  nerve  and  retina.  The  demand  for 
methyl  alcohol  has  increased  the  price  and  the  pure- 
food  laws  have  discouraged  the  practice.  Most  of  the 
ethyl  alcohol  made  for  industrial  use  is  produced  by 
the  fermentation  of  molasses,  after  which  the  spirit  is 
distilled  off  and  cooled.  It  is  denatured  by  adding 
to  it  ill-smelling  substances  that  make  it  unfit  to 
drink.  Pyridine  (C5H5N),  which  smells  like  stale 
tobacco-smoke  with  remorse  added  to  it,  is  often 
used  for  this  purpose.  We  have  never  heard  of  any 
one  with  a  craving  for  it.  The  United  States  Treasury 
Department  provides  a  long  list  of  denaturing  agents 
to  meet  the  different  industrial  uses  to  which  the  al- 
cohol is  to  be  put.  It  has  already  come  into  consid- 
erable use  for  cooking-stoves  and  for  lighting  with 
Welsbach  mantles. 

GLYCOL   AND   GLYCERIN 

We  have  observed  how,  by  substituting  OH  for  H 
in  a  paraffin,  we  get  an  alcohol.  Now  among  the  vari- 

261 


EVERYMAN'S    CHEMISTRY 

ous  idiosyncrasies  of  carbon  is  the  fact  that  it  does  not 
like  to  have  more  than  one  OH  group  attached  to 
one  carbon  atom.  You  may,  by  chemical  strategy, 
succeed  in  getting  a  second  OH  attached  to  it,  but  it 
will  not  stay,  and  time  and  again,  when  you  think  you 
are  likely  to  succeed,  the  whole  thing  will  play  a  trick 
on  you  and  break  down  into  something  entirely  dif- 
ferent. But  we  have  those  alcohols  with  one  OH, 
and  they  act  something  like  an  alkali;  they  produce 
salts,  or  esters,  as  they  are  called  in  organic  chemistry, 
with  acids.  We  do  not  need  to  put  more  than  one 
OH  group  upon  one  carbon  atom;  there  is  plenty  of 
room  for  more.  So  let  us  add  several  OH  groups  and 
see  what  happens: 


CH,  OH  Nothing  more  here  in  fhe 

Methane   •  Mefnyl  Alcohol      OH  line,  only  one  C  atom 


iy  C2HSOH  C-OH  C-OH 

/  Ethyl  Alcohol  C—OH  C—H 

fthane  \tt  I  x(?/7 

Glycol  C-OH 

CLJ  /"*    t-l  r\U  ^"A/ 

jfig  L,j/77(J/7  112 

Propane  Propyl  Alcohol         Glycerol  or  Glycerin 

Here  we  have  something  sweet  and  sticky  and  that 
acts  in  a  mild  way  as  a  base.  Glycol  is  a  dihydric 
alcohol,  and  glycerin  is  a  trihydric  alcohol.  In  the 
place  of  each  of  those  OH  groups  an  acid  radical  can 
take  its  place,  and  this  is  the  great  base  of  oils  and 
fats  that  we  find  in  nature.  It  is  this  one  particular 
body,  C3H8O3,  glycerol,  or  glycerin,  as  it  is  more 
popularly  called,  that  we  find  in  all  fats  and  oils, 
instead  of  a  whole  series  running  up  and  down  the  list. 
We  shall  meet  its  cousins  of  many  atoms  when  we 
come  to  sugars,  but  for  the  present  we  are  busy  with 
nature's  great  organic  base.  It  is  sweet  and  sticky 

262 


ALCOHOLS   AND    SOME    RELATIVES 

and  very  hygroscopic  or  deliquescent,  which  means 
that  it  has  a  grand  thirst  for  water.  Fats  and  oils 
that  are  esters  or  salts  of  glycerin  with  organic  acids 
are  also  called  glycerides.  Boil  up  a  fat  with  a  caustic 
alkali,  such  as  caustic  soda,  and  you  produce  soap  and 
glycerin. 

Aside  from  its  use  in  medicine,  chiefly  as  an  emol- 
lient, and  in  chemical  industry,  in  dyeing  and  printing, 
and  for  anti-freezing  compounds,  its  greatest  use  is  in 
nitroglycerin  for  explosives.  In  the  place  of  each 
of  those  three  OH  groups,  nitric  acid  may  hook  itself 
on  and  we  may  have  mono-,  di-,  or  tri-nitroglycerin. 
For  explosives  the  trinitrate  is  employed,  and  the 
formula  is  C3H5(NO3)3.  It  is  a  heavy,  oily  liquid 
having  a  sickly  odor,  and  after  it  is  carefully  washed 
and  brought  to  a  pure  state  it  does  not  explode  spon- 
taneously. Mixed  with  infusorial  earth,  which  is  in 
effect  very  finely  divided  particles  of  silicon  dioxide, 
SiO2,  it  forms  a  soft,  plastic  mass  which  can  be  molded 
in  the  hands.  This  dynamite  is  about  25  per  cent, 
infusorial  earth  and  75  per  cent,  nitroglycerin.  This 
was  Alfred  Nobel's  original  dynamite;  now  many 
different  mixtures  are  made,  including  oxidizing 
agents  and  nitrocellulose. 

ESTERS   AND   ETHERS 

If  an  acid  with  its  hydrogen  ion  meets  a  base  with 
its  OH  ion  in  inorganic  chemistry,  a  salt  is  formed, 
and  the  H  of  the  acid  and  the  OH  of  the  base  combine 
to  produce  H2O,  or  water.  In  organic  chemistry  the 
process  is  much  slower;  the  OH  groups  of  the  alcohols 
and  other  bodies  which  contain  them  do  unite  with  the 
H  of  the  acids  to  produce  water,  H2O,  while  the  rest  of 
the  acid  and  the  alcohol,  glycerol,  or  whatever  it  may 
18  263 


EVERYMAN'S    CHEMISTRY 

be,  slowly  combine  into  what  is  called  an  ester.  Ester 
is  the  expression  for  salt  in  organic  chemistry.  Whether 
this  name  came  from  the  Bible  or  not  is  more  than  I 
can  say,  except  that  some  of  the  esters  are  fragrant 
and  have  strong  fruity  odors.  Many  perfumes,  whether 
natural  or  artificial,  are  complex  ethers  and  esters. 
And  Esther  of  Holy  Writ,  you  may  recall,  was  puri- 
fied, "to  wit,  six  months  with  oil  of  myrrh  and  six 
months  with  sweet  odors  and  with  other  things/'  but 
just  how  pious  the  first  man  was  who  called  these  salts 
esters  we  do  not  know. 

There  are  also  esters  of  inorganic  acids.  Thus  if 
we  bring  alcohol  and  nitric  acid  together  we  have  an 
ester. 


C2H6OH     +    HNpa     =     H20     + 
ethyl  nitric  water  ethyl 

alcohol  acid  nitrate 

Ethers.  If  we  take  two  molecules  of  an  alcohol, 
and  then  from  the  two  take  one  molecule  of  water, 
leaving  one  atom  of  oxygen  as  a  kind  of  hinge  to  con- 
nect them  together,  we  have  an  ether.  Let  us  do 
that  in  two  operations  : 

C2H6OH     +     H2SO4     =     C2H6HSO4     +    H2O 
ethyl  sulphuric          ethyl  sul-  water 

alcohol  acid  phuric  acid 

Now  let  us  add  more  alcohol,  and  we  have 


ethyl  sul-  ethyl          diethyl    sulphuric 

phuric  acid        alcohol  ether        acid 

Observe,  please,  that  you  get  the  sulphuric  acid  back 
again,  so  that  a  little  of  it  goes  a  long  way  in  making 
ether. 

264 


ALCOHOLS  AND    SOME   RELATIVES 

The  number  of  possible  ethers  is  twice  as  many  as 
there  are  alcohols,  because  two  different  alcohols  may 
be  connected  up  by  an  oxygen  atom.  The  above, 
diethyl  ether,  is  the  one  best  known  and  is  used  in  the 
production  of  anesthesia. 


ALDEHYDES    AND    KETONES 

If  we  take  two  atoms  of  hydrogen  from  an  alcohol 
we  get  what  is  called  the  corresponding  aldehyde,  and 
if  we  add  an  atom  of  oxygen  to  the  aldehyde  we  get 
the  corresponding  acid.  The  name  aldehyde  indicates 
dehydrogenated  alcohol,  or  alcohol)  cM;yd(rogenatus), 
and  that  which  is  best  known  is  formaldehyde,  the 
first  of  the  series,  corresponding  to  formic  acid,  which 
in  turn  corresponds  to  the  methane  group.  Methyl 
alcohol  is  CH3OH,  formaldehyde  is  CH2O,  formic  acid 
is  CHOOH.  Ethyl  alcohol  is  C2H6OH,  ethyl  aldehyde 
is  C2H3OH,  and  acetic  acid  is  C2H3.O.OH. 

Formaldehyde  is  a  gas,  soluble  in  water,  and  every- 
body knows  its  unpleasant  smell.  It  is  an  excellent 
antiseptic  and  an  active  poison.  It  is  produced  from 
wood  alcohol  (methyl  alcohol).  It  has  the  trick  of 
polymerizing,  as  it  is  called — that  is,  of  multiplying 
up  its  molecules  into  other  bodies  by  doubling,  tripling, 
quadrupling,  etc.,  until  molecules  of  a  very  high  num- 
ber of  atoms  are  obtained.  If  brought  into  contact 
with  carbolic  acid,  it  forms  a  precipitate,  and  when 
this  precipitate  is  heated  and  pressed  under  just  the 
right  conditions  the  well-known  substance  Bakelite 
and  other  similar  products  are  made.  The  method 
is  just  the  one  you  would  expect.  Here  we  have  a 
body,  which  by  heating,  to  loosen  up  the  hooks  of  the 
atoms  in  the  molecule  and  by  pressing  at  the  same 

265 


EVERYMAN'S   CHEMISTRY 

time,  we  get  new  molecules  with  much  larger  numbers 
of  atoms  in  them.  The  higher  series  are  gums,  and 
Bakelite  in  its  final  form  is  one  of  the  most  inert  sub- 
stances known  in  regard  to  acids,  alkalies,  and  elec- 
tricity. It  looks  like  amber,  but  can  be  colored  and 
made  opaque;  it  is  very  largely  used  in  electrical  ap- 
paratus; it  makes  excellent  billiard-balls,  being  some- 
what livelier  than  ivory,  and  is  used  for  pipe-stems 
and  all  other  things  for  which  amber  is  employed. 

Ketones  have  the  same  general  formula  as  the  alde- 
hydes, but  the  arrangement  of  the  atoms  in  the  mole- 
cule is  different.  Acetone,  the  first  of  the  series,  and 
the  most  popularly  known,  is  represented  by  CH3- 
CO.CH3.  It  is,  you  observe,  a  methyl  group  on  either 
side  of  a  CO  group.  There  is  one  free  hook  to  each  of 
the  CH3  radicals,  and  there  are  two  left  over  from  the 
CO  group  of  atoms.  Acetone  is  prepared  from  acetate 
of  lime  and  is  used  in  chemical  industry.  It  is  miscible 
with  water  in  all  proportions,  and  is  especially  valuable 
as  a  solvent.  Acetate  of  lime,  you  may  recall,  is  a 
product  of  the  distillation  of  wood.  A  new  method 
of  producing  acetone  is  by  means  of  a  yeast  which 
ferments  sugar  into  acetone,  hydrogen,  and  other 
bodies.  Over  half  of  the  world's  production  of  acetone 
is  made  in  one  works  from  acetic  acid,  which,  in  turn, 
is  obtained  from  the  oxidation  of  ethyl  alcohol.  Great 
quantities  are  needed  in  the  manufacture  of  cordite. 

As  might  be  expected,  the  halogens  take  the  place 
of  hydrogen  in  these  hydrocarbons,  according  to  their 
nature.  Fluorine  is  very  energetic,  chlorine  less  so, 
and  iodine  will  not  react  directly  with  them,  but 
requires  a  little  chemical  coaxing  to  bring  it  into  com- 
bination. We  shall  mention  only  a  few  of  these 
products. 

Chloroform  is  methane,  CH4,  with  three  hydrogen 

266 


ALCOHOLS  AND   SOME   RELATIVES 

atoms  substituted  by  chlorine  to  CHC13.  It  is  not  a 
very  stable  liquid,  decomposing  under  the  influence 
of  light  and  air,  and  is  always  preserved  by  ethyl 
alcohol.  Its  use  is  chiefly  as  an  anesthetic,  but  it  has 
also  valuable  solvent  properties. 

Carbon  tetrachloride  we  have  already  described,  and 
iodoform,  CHI3,  is  a  yellow  crystalline  substance  used 
in  surgery  as  an  antiseptic. 


XXII 

FATS,   OILS,   AND  THEIR  PRODUCTS 

How  Nature  Sometimes  Makes  a  Mistake — Need  of  Fats — A  General 
Petition  for  Cleanliness — Refining  Oils — List  of  Well-known  Oils 
— Hardening  Oils — Theory  and  Practice — Oleomargarine — Noth- 
ing to  Be  Afraid  of — Soap — Theory — Practice — Twitchell  Process 
— Toilet  Soaps — Washing  Clothes — Improvements 

WE  have  discussed  at  some  length  the  various 
fatty  acids  and  we  have  also  considered  the 
base  of  fats  and  oils,  which  is  glycerin.  Nature  has  a 
way  of  storing  up  energy  in  fats.  They  have  a  high 
value  in  producing  body  heat  and  body  energy,  and 
they  form  layers  of  protective  tissue  which  serve  as 
storehouses  to  be  drawn  on  in  emergencies.  Of  course, 
nature  does  not  always  get  just  the  right  information 
and  sometimes  proceeds  to  provide  layer  upon  layer 
of  fat  where  it  is  neither  wanted  nor  needed.  Metab- 
olism is  an  odd  series  of  processes,  and  we  do  not 
of  necessity  grow  fat  by  eating  glycerides.  On  the 
other  hand,  fatty  degeneration  may  set  in  at  any 
time,  and  the  most  abstemious  and  athletic  man  may 
puff  up  like  a  porker  for  no  reason  that  can  be  ascer- 
tained, or,  at  all  events,  for  no  reason  that  will  satisfy 
him.  There  is  also  a  legend  to  the  effect  that  ladies 
sometimes  grow  aweary  of  the  increasing  abundance 
of  their  charm. 

In  this  chapter,  however,  we  are  not  discussing 
human  fat,  but  rather  that  of  lower  animals  which  is 

268 


FATS,  OILS,  AND  THEIR   PRODUCTS 

sold  as  lard  or  tallow,  and  the  fats  of  plants,  or  rather 
seeds,  which  are  usually  oils.  Both  lard  and  tallow 
are  chiefly  stearates  of  glycerin  and  the  principal  ob- 
servation that  has  been  made  concerning  them  during 
the  past  few  years  is  that  there  is  not  enough  to  go 
round;  hence  the  rise  in  price.  We  must  have  fats, 
however,  and  fortunately  a  way  has  been  discovered 
to  give  us  all  the  hard  fats  we  need  through  the  hydro- 
genation  of  oils.  We  should  remember  that  these  oils, 
whether  from  plants  or  animals,  are  very  similar  in 
constitution  and  that  they  need  good  treatment,  espe- 
cially if  they  are  to  be  hardened  into  fats  for  eating. 
We  do  not  let  a  hog  lie  around  after  it  has  been  slaugh- 
tered before  the  lard  is  removed,  and  no  more  should 
vegetable  oils  be  allowed  to  degenerate  before  they 
are  refined.  Oils  must  be  fresh  and  the  speed  of  refin- 
ing as  well  as  the  methods  by  which  they  are  obtained 
are  great  factors  in  their  quality. 

A  large  amount  of  palm  and  cocoanut  oil  comes 
from  the  tropics  in  very  bad  condition,  although  of 
late  efforts  have  been  made  to  improve  conditions 
under  civilized  control.  But  reforms  are  slow  in  com- 
ing about.  Not  long  ago  some  oil-presses  were  sent 
to  the  tropics  to  press  out  palm  and  cocoanut  oils,  and 
word  came  back  that  "the  presses  were  too  heavy 
for  women  and  children  to  operate."  Millions  of 
dollars  would  be  saved  annually  in  the  United  States 
alone  if  oils  were  properly  instead  of  carelessly  ren- 
dered. Peanut  oil,  for  instance,  made  of  Algerian 
peanuts  and  pressed  in  France,  comes  in  splendid 
shape.  Domestic  peanuts,  at  the  present  writing,  are 
often  not  even  husked  before  pressing,  and  they  are 
frequently  pressed  in  cotton-seed  oil-presses  that  have 
not  even  been  cleaned  before  the  operation.  Let  us 
hope  that  this  defect  may  soon  be  corrected. 

269 


EVERYMAN'S   CHEMISTRY 

Cotton-seed  oil  has  the  habit  of  growing  rancid  in 
the  seed  if  the  weather  is  wet;  therefore  the  cotton- 
oil  crop  is  always  poor  after  a  wet  season.  Corn-oil, 
which  contains  a  considerable  amount  of  unsaponi- 
fiable  matter,  is  usually  handled  in  a  clean  manner  and 
it  is  growing  in  favor  as  an  edible  oil. 

In  refining  oils  it  is  preferable  to  employ  physical 
methods  rather  than  chemical  reagents,  because  oils 
are  so  delicate  and  complex  that  it  is  easy  to  tear  them 
to  pieces,  constitutionally,  with  acids  and  alkalies. 
There  are,  however,  nearly  always  some  free  fatty 
acids  in  oils,  and  these  increase  as  time  goes  on. 
To  avoid  this  increase  it  is  necessary  to  add  a  slight 
amount  of  alkali  to  neutralize  them  in  refining.  This, 
of  course,  produces  soap,  which  is  precipitated  usually 
with  clay. 

After  oil  is  pressed  from  nuts  or  seed  it  should  be 
allowed  to  settle  immediately  and  the  pulp  and  albu- 
minous matter  precipitated  with  clay.  Pulp  is  vexa- 
tious stuff  in  oils;  it  darkens  them  and  makes  them 
rancid.  The  color  and  turbidity  are  removed  by  ful- 
lers' earth,  and  the  odor,  except  that  of  fullers'  earth, 
is  removed  by  passing  through  charcoal.  The  earthy 
taste  and  smell  are  blown  out  by  steam.  Some  oils  are 
bleached  and  their  pigments  oxidized  by  blowing  air 
through  them.  Linseed  and  soya-bean  oils  are 
bleached  by  heating  up  to  200°  centigrade,  whereby 
the  pigments  are  carbonized  and  the  color  grows  light. 

An  interesting  process  is  that  discovered  and  pat- 
ented by  Prof.  Charles  Baskerville,  of  New  York, 
which  provides  for  immediate  refining  of  oils  after 
pressing — a  great  desideratum.  The  oils,  after  press- 
ing, are  run  into  a  settling-tank  and  there  treated  with 
cellulose,  usually  in  the  form  of  wood-pulp,  and  a 
slight  amount  of  soda.  The  pulp  absorbs  the  coloring- 

270 


FATS,  OILS,  AND  THEIR   PRODUCTS 

matter  and  other  impurities,  together  with  the  soap 
produced  by  the  soda,  and  is  separated  from  the  oil 
by  filter  presses. 

The  following  are  some  of  the  principal  oils  that 
come  upon  the  markets  of  the  United  States: 

Lard  and  Tallow  Oils.  Almost  entirely  used  in  the 
production  of  artificial  butter. 

Cotton-seed.  The  old  stand-by.  The  largest  use 
is  for  foods.  The  next  single  use  is  to  make  "pure 
Castile  soap  from  olive-oil.  The  olives  from  the 
Mount  of  Olives."  Marseilles,  France,  is  the  head- 
quarters for  Castile  soap,  and  the  French  use  chiefly 
cotton-seed,  peanut,  and  sesame  oils  for  their  product. 
It  is  hardened  into  "Crisco"  and  similar  products, 
and  Doctor  Wesson  has  succeeded  in  refining  it  into  a 
very  good  salad-oil. 

The  Olive  is  needed  in  certain  industries  as  well  as 
for  salads  and  cooking.  The  Latin  and  Mediterranean 
peoples  cook  with  oil,  the  Teutonic  and  Slavic  peoples 
with  hard  fats.  The  line  is  as  clearly  drawn  as  is  the 
line  of  language  which  divides  the  races. 

The  Soya-bean  is  a  very  important  oil.  It  comes 
from  China  and  Indo-China,  although  it  could  also 
be  grown  in  many  parts  of  the  United  States.  It  is 
edible,  is  good  soap  stock,  and  it  is  said  to  have  fair 
drying  qualities.  There  appears  to  be  a  great  future 
for  the  soya  bean. 

Peanut  is  a  good  substitute  for  cotton-seed  oil  and 
should  have  a  good  future.  It  is  edible,  hardens  well, 
and  is  good  soap  stock. 

Fish-oil  is  sometimes  used  in  cheap  mixed  paints; 
it  hardens  well  and  loses  its  odor  in  the  process,  pro- 
vided it  is  thoroughly  done. 

Castor-oil  is  a  medicine,  a  lubricant,  and  used  in  the 
dyeing  industry  as  Turkey-red  oil. 

271 


EVERYMAN'S    CHEMISTRY 

Cocoanut-oil  has  advantages  in  soap-making.  It 
contains  some  low,  fatty  acids,  of  which  the  sodium 
esters,  or  soaps,  are  somewhat  soluble  in  hard  and  salt 
water.  This  makes  cocoanut-oil  soaps  available  over 
a  wide  range. 

Cocoa  butter  is  that  which  is  pressed  from  the 
chocolate  bean  and  is  the  most  expensive  of  the  fats 
mentioned.  It  is  used  in  the  manufacture  of  confec- 
tionery and  for  toilet  preparations. 

Chinese  vegetable  tallow  is  an  odd  fat  which  usually 
comes  here  in  rather  bad  shape  It  is  a  good  soap 
stock,  but  it  has  an  odd  peculiarity  that  may  make 
it  a  great  convenience  to  some  inventor  who  wants 
just  this  quality.  Like  water  and  antimony,  it  ex- 
pands as  it  hardens,  so  that  if  it  is  melted  and  poured 
into  a  glass  or  earthenware  vessel  of  any  kind  it  will 
break  the  vessel  as  it  hardens.  It  is  hard  at  ordinary 
temperatures.  The  peculiarity  of  hardening  as  it 
expands  would  make  it  valuable  in  taking  the  exact 
shape  of  strong  molds,  just  as  antimony  causes  type 
metal  to  take  the  complete  form  in  the  matrix. 

Hardening  oils,  or  hydrogenation  of  fats,  as  it  is 
called,  is  one  of  the  noteworthy  accomplishments  of 
modern  industrial  chemistry.  As  a  research  achieve- 
ment it  ranks  in  importance  with  the  cracking  of 
petroleum  to  produce  gasolene  and  with  the  flotation 
process  for  concentrating  ores. 

Let  us  recall  what  we  observed  of  the  comparison 
between  fatty  acids  and  those  of  the  oleic  group  and 
note  that  their  only  difference  is  that  of  two  atoms  of 
hydrogen.  For  instance : 

Propionic  Acid  (fatty  group)  is  C2H5.COOH. 
Acrylic  Acid  (oleic  group)  is  C2H3.COOH. 

Stearic  Acid  (fatty  group)  is  Ci7H35COOH.  Oleic 
Acid  (oleic  group)  is  Ci7H33.COOH. 

272 


FATS,  OILS,  AND  THEIR  PRODUCTS 

Now  there  are  other  acids  found  in  fats  and  oils,  but 
chiefly  in  oils,  and  some  contain  four  atoms  of  hydro- 
gen less  than  the  corresponding  fatty  acid.  Linoleic 
acid  (from  linseed-oil)  is  six  hydrogen  atoms  shy,  and 
among  fish-oils  there  is  one  acid  that  has  eight  hydro- 
gen atoms  less  than  the  fatty  acid  with  the  same  num- 
ber of  carbon  atoms.  Linseed  and  fish  oils  have  dry- 
ing qualities,  which  may  be  due  to  these  unsaturated 
bodies,  but  linseed-oil  is  far  better. 

If,  then,  in  the  hard  fats  the  most  of  the  acids  are 
like  stearic,  which  has  all  the  hydrogen  it  can  carry — • 
and  most  of  the  acids  in  the  oils  have  not  as  much 
hydrogen  as  they  can  carry — it  follows  that  if  we  can 
intrigue  a  couple  or  more  of  hydrogen  atoms  into  the 
molecules  of  these  oils,  getting  them  into  their  right 
places,  we  shall  shift  the  series  over  from  the  unsatis- 
fied oleic  and  lower  groups  into  fatty  acids.  In  other 
words,  if  the  only  difference  between  stearic  or  fat 
acid  and  oleic  or  oil  acid  is  hydrogen,  then  if  we  put 
the  hydrogen  in  we  shall  change  the  oil  to  a  fat.  The 
glycerin  is  not  interested  in  the  operation;  it  is  just 
as  well  satisfied  if  mated  to  the  one  as  it  is  to  the  other. 
Indeed,  it  is  often  combined,  as  we  have  said,  with 
two  or  even  three  different  acids  at  each  of  its  avail- 
able places.  Getting  the  necessary  hydrogen  atoms 
into  the  oil  molecules  is  the  trick  we  should  like  to 
turn,  although  we  can  let  hydrogen  gas  bubble  through 
cotton-seed  or  palm  or  soya-bean  or  olive  or  peanut 
or  any  other  oil  to  our  heart's  content,  and  nothing 
will  happen.  But  here  comes  the  catalyst:  some 
very  finely  divided  nickel,  for  instance,  or  platinum  or 
palladium  (both  of  which  are  too  expensive)  will  intro- 
duce the  H  atoms.  These  are  led  into  the  oil  into 
just  the  place  where  they  are  needed,  along  with 
the  hydrogen,  and  up  comes  your  oil  as  nice,  clean, 

273 


EVERYMAN'S    CHEMISTRY 

white  fat.  It  is  fat,  stearic,  palmitic,  etc.,  glycerol 
esters. 

When  we  consider  the  rate  at  which  meats,  including 
their  fats,  have  increased  in  cost  of  late  years  and  the 
increase  of  the  population  of  cities,  always  calling  for 
more  meat  and  more  fat,  we  can  appreciate  the  value 
of  this  invention,  which  will  turn  nearly  any  good, 
pure,  non-poisonous  oil  into  edible  fat — substantially 
into  lard. 

So  far,  nickel  has  proved  to  be  the  great  catalyst 
for  this  purpose,  and  the  reason  why  it  must  be  very 
finely  divided  is  that  it  appears  that  the  H  will  go 
into  combination  only  when  the  particles  of  Ni,  oil, 
and  H  are  all  three  in  contact.  Another  excellent 
reason  is  that  it  will  not  work  unless  the  Ni  is  very 
finely  divided,  finer  than  we  can  grind  it.  So  it  is 
precipitated  out  of  a  nickel  salt  in  a  condition  fine 
enough  to  do  the  work.  An  interesting  feature  is  that 
the  nickel  apparently  gets  tired  and  refuses  to  work 
after  a  while.  Then  it  must  be  heated  to  drive  off 
the  oil,  whereby  it  also  becomes  oxidized.  Next  it  is 
heated  again  in  a  current  of  hydrogen  and  thus  re- 
duced. Then  it  is  ready  for  business  as  before. 

After  the  operation  of  hardening  oils  is  over  there  is 
some  nickel  that  remains  in  the  fat,  and  it  is  so  finely 
divided  that  it  cannot  be  removed.  But  this  need 
not  worry  us.  There  is  less  nickel  in  these  fats  than 
is  obtained  by  cooking  in  a  nickel-plated  chafing-dish. 
It  is  estimated  that  not  over  six  parts  of  nickel  remain 
in  10,000,000  parts  of  fat. 

Hydrogen  is  very  slightly  soluble  in  oils,  so  that  a 
general  agitation  or  mixing  up  is  necessary  to  bring 
about  the  triple  contact.  Pressure  also  speeds  up  the 
reaction,  but  it  is  hard  to  keep  the  hydrogen  in  the 
autoclaves  under  pressure.  To  make  an  autoclave  or 

274 


FATS,  OILS,   AND  THEIR   PRODUCTS 

pressure  vessel  with  an  agitator  air-tight  is  quite  a 
task;  the  attempt  to  make  it  hydrogen-tight  is  more 
than  likely  to  involve  unprofitable  and  unsuccessful 
profanity. 

The  modern  method  is  to  attach  the  nickel  to  some 
light,  inert  substance  to  keep  it  afloat,  and  this  aids 
in  effecting  the  triple  contact.  A  fairly  high  tempera- 
ture is  necessary — 180°  to  190°  centigrade  is  best.  At 
100°  centigrade  the  operation  proceeds  very  slowly. 
There  are  a  great  many  patents  covering  various 
processes  in  the  art,  and  at  the  present  writing  oppos- 
ing interests  are  engaged  in  trial  at  law  to  determine 
their  rights  and  privileges. 

Hydrogenation  may  be  stopped  at  any  stage,  and 
very  hard  fats  may  be  mixed  with  untreated  oils  so 
that  any  degree  of  hardness  or  softness  may  be  ob- 
tained. The  principal  use  of  hardened  oils  is  for 
cooking  and  for  use  in  soaps.  Soya-bean,  peanut,  and 
corn  oils  are  coming  into  favor  as  edible  products 
along  with  cotton-seed  oil. 

OLEOMARGARINE. — Three  kinds  of  this  artificial  but- 
ter are  produced : 

1.  White; 

2.  Tinted  (natural  color); 

3.  Colored  (artificially). 

The  best  is  the  white,  made  from  the  best  beef  fat, 
neutral  lard,  with  some  cotton-seed  or  peanut  oil. 
The  tinted  includes  some  of  the  yellower  oleo  oils, 
while  the  colored  is  colored  with  annatto,  a  coloring- 
matter  obtained  from  the  seed  petals  of  the  annatto 
tree  of  South  America.  The  ingredients  are  similar  to 
those  of  the  white. 

The  so-called  oleo  oils  are  the  oils  of  lard  and  tallow. 
They  are  expressed  in  the  lard  refineries  and  then 

375 


EVERYMAN'S   CHEMISTRY 

beaten  up  or  emulsified  with  milk.  It  is  very  impor- 
tant that  a  good,  rich  grade  of  milk  be  used  which  is 
first  pasteurized  and  then  allowed  to  " ripen"  or  grow 
sour,  just  as  sour  cream  is  used  for  butter.  The  oils  are 
heated  and  the  fats  melted  under  carefully  regulated 
temperatures,  then  weighed  off  and  run  into  the  churn 
or  emulsifier,  which  contains  ripened  milk.  The 
churning  lasts  from  fifteen  minutes  to  an  hour,  and 
then  the  whole  is  run  into  a  tank  under  a  spray  of  ice- 
water,  whereupon  the  butter  floats  on  the  ice-water 
and  milk  and  is  skimmed  off.  These  tanks  are  called 
crystallizing  tanks.  The  butter  is  left  some  time  in 
containers  to  drain  and  to  take  on  the  flavor  of  the 
milk  that  is  left  in  it.  Then  it  is  worked  like  real 
butter,  salted,  and  packed  for  sale. 

The  process  as  carried  on  in  large  factories  is  a  clean 
one,  and  as  the  fats  are  practically  sterilized  and  the 
milk  pasteurized,  oleomargarine  does  not  carry  the 
hazard  of  the  bacilli  of  disease  that  may  be  found 
in  defective  but  genuine  butter. 

Unsalted  oleomargarine  has  very  little  taste  and 
is  not  so  good  a  substitute  for  fresh  or  unsalted  butter 
as  it  is  for  that  which  is  salted.  The  differences  in 
taste  are  greater. 

Oleomargarine  yield  nearly  twice  the  amount  of  food 
principle  computed  in  calories  compared  with  that  pro- 
vided by  butter,  although  butter  fat  also  carries  minute 
peculiar  bodies  which  some  maintain  are  needed  in 
animal  metabolism.  Some  manufacturers  provide 
along  with  the  best  white  oleomargarine  little  tubes  of 
annatto,  so  that  the  thrifty  housewife  may  color  her 
artificial  butter  as  she  desires  it.  The  tax  on  the  white 
and  tinted  product  in  the  United  States  is  one-fourth 
of  a  cent  per  pound;  the  tax  on  the  colored  oleo- 
margarine is  ten  cents  per  pound.  There  was  pro- 

276 


FATS,  OILS,  AND  THEIR   PRODUCTS 

duced  in  the  United  States  from  April  i,  1915,  to 
April  i,  1916,  147,156,197  pounds  of  oleomargarine. 

SOAP. — Fats,  as  we  know  them,  whether  liquid,  as 
olive  or  cotton-seed  oil,  or  solid,  as  beef  suet,  you  will 
remember,  are  esters  or  salts  of  the  higher  fatty  or 
oleic  acids  with  glycerin.  When  these  are  boiled 
with  an  alkali  such  as  caustic  soda,  we  get  the  sodium 
salts  or  esters  of  the  fatty  acids,  and  that  is  soap.  Any 
strong  alkali  will  produce  a  soap,  and  the  process  of 
splitting  a  fat  into  its  acid  parts  and  glycerin  is  called 
saponification.  The  by-product  is  glycerin.  Potash 
soap  is  soft;  sodium  soap  is  hard,  and  that  is  the 
product  that  we  use  every  day. 

What  happens,  then,  when  we  wash  our  hands  and 
get  rid  of  the  dirt  with  the  soap?  In  the  first  place, 
a  certain  amount  of  our  own  fat  oozes  out  through 
the  skin  constantly,  through  the  sweat-glands — not 
through  the  pores,  as  many  believe.  This  fatty 
sweat  is  sticky,  and  holds  the  dirt  on.  Now  soap, 
being  a  salt  of  a  metallic  alkali  with  a  high  fatty  acid, 
is  not  a  very  robust  compound;  the  base  is  strong, 
but  the  acid  is  weak.  When  dissolved  in  water  it  dis- 
sociates in  part  to  free  acid  and  free  alkali.  If  we  add 
more  water  to  the  solution,  more  free  stearic  or  pal- 
mitic or  whatever  the  acids  may  be  are  freed,  as  is 
more  alkali,  but  the  additional  water  keeps  it  in  dilu- 
tion, so  that  we  never  get  very  much  free  alkali  from 
a  good  soap.  The  free  acid  combines  with  another 
molecule  of  soap  and  produces  a  light,  insoluble  com- 
pound, which  is  suds.  The  suds  act  as  a  mechanical 
carrier  and  carry  away  the  particles  of  dirt  which  have 
been  liberated  by  the  just-enough-but-not-too-much 
free  alkali.  The  free  alkali  attacks  the  grease  it  finds 
and  makes  more  soap  of  it.  That  is  the  theory,  or 

277 


EVERYMAN'S   CHEMISTRY 

at  least  a  theory,  which  seems  reasonable.  Others 
maintain  that  soap  acts  as  a  cleaner  because  of  its 
lubricating  and  solvent  power.  Let  us  not  dispute 
over  it. 

Caustic  soda  or  sodium  carbonate  would  do  just 
as  well  so  far  as  loosening  up  the  dirt  is  concerned. 
The  trouble  is  we  should  get  the  alkaline  solution  too 
strong  and  injure  the  skin  or  the  cloth.  The  great 
merit  of  soap,  so  far  as  its  free  alkali  is  concerned,  is 
its  moderation,  its  temperance.  Then  the  lather  is  a 
great  convenience. 

When  soap  is  made  by  boiling  up  fats  with  caustic 
soda  the  product  is  driven  out  of  solution  by  adding 
salt.  Then  the  soap  floats  on  top  in  flakes  and  the 
glycerin  and  salt  water  are  below.  When  the  soap 
is  pressed  out  it  sinks,  but  it  can  be  made  to  float  by 
blowing  air  into  it. 

Now  you  may  recall  why  hard  water  is  undesirable 
for  use  with  soap.  We  explained  how  the  lime  and 
magnesia  that  it  contains  change  place  with  the  so- 
dium in  the  esters  of  the  fatty  acids  and  produce  lime 
and  magnesia  soaps  which  are  insoluble,  while  we  were 
discussing  water. 

An  improved  method  of  saponification  or  the  split- 
ting of  fats  is  the  process  of  Dr.  Ernest  Twitchell,  of 
Cincinnati.  He  provides  a  catalyst  (a  "saponifier," 
he  calls  it),  consisting  of  a  fatty  acid  coupled  up  with 
naphthalene,  and  this  is  further  treated  with  sulphuric 
acid,  so  that  a  fatty,  aromatic,  sulphonic  acid  is  pro- 
duced. A  very  little  of  this — }4.  of  i  per  cent,  of  the 
weight  of  the  fat — will  effectively  split  the  entire 
batch.  The  glycerin  then  contains  no  salt  and  very 
few  other  impurities,  while  the  fatty  acids,  even  if  pro- 
duced from  low-grade  fats,  may  be  purified  by  distilla- 
tion. Soap  is  then  made  by  bringing  the  acids  into 

278 


FATS,  OILS,  AND  THEIR  PRODUCTS 

contact  with  soda  ash  instead  of  the  more  expensive 
caustic  soda  that  is  used  in  the  old  method.  The 
Twitchell  process  is  in  large  use  by  progressive  manu- 
facturers. 

Soap  is  soap — softer  if  made  with  potash  and  harder 
if  made  with  soda.  Roughly  speaking,  cheap  soaps 
are  likely  to  be  made  of  vegetable  fats  to  a  greater 
extent  than  expensive  products,  and  yet  very  often 
the  big,  yellow  cakes  of  the  laundry  and  the  scented 
Thing  of  Perfection  in  the  boudoir  are  made  from  the 
same  stock.  Many  French  persons  always  use  Amer- 
ican soaps  on  the  ground  that  they  are  the  best. 
Many  Americans,  on  the  other  hand,  prefer  French 
soaps  for  toilet  use  on  the  ground  that  they  are  still 
better.  Others  buy  whichever  costs  the  most  in  the 
same  search  after  perfection.  Now  soap,  I  repeat,  is 
soap,  and  the  things  you  pay  for  in  fancy  soaps  are 
things  to  please — perfume,  rosin,  filler,  and  emollients 
of  one  sort  or  another,  not  forgetting  the  wrapper. 
It  is  not  chemistry  that  makes  a  piece  of  good,  neutral 
soap  with  no  free  alkali  a  little  scented  nubbin  worth 
fifty  cents ;  it  is  art. 

Washing  clothes  or  laundering  is  an  art  that  has 
not  changed  in  any  major  way  for  many  years.  There 
are  the  clothes  and  the  dirt  on  the  one  hand  and  soap 
and  water  on  the  other,  and  the  best  we  know  how  to 
do  is  to  rub  them  all  together,  rinse  them  out,  and 
dry  them.  Then  after  they  are  bleached,  starched, 
and  ironed,  they  are  ready  for  use  again.  There's 
nothing  new  in  this.  But  in  minor  details  there  have 
been  many  changes,  and  it  is  fair  to  say  that  greater 
improvements  have  been  made  in  the  public  laundries 
than  in  the  laundry  of  the  household. 

The  general  practice  in  commercial  laundries  is  first 
to  check  and  mark  the  goods.  Fine  linens  that  may 
19  279 


EVERYMAN'S   CHEMISTRY 

not  be  marked  up  are  put  into  nets  and  each  net  bears 
a  tag.  Then  the  wash  is  made  up  into  lots  and  these 
lots  go  through  the  whole  process  as  single  batches. 
Each  lot  then  is  first  put  through  the  wheel  in  cold 
water,  soap,  and  soda.  To  about  240  pounds  of 
water  (30  gallons)  X  pound  of  soda  and  i  pound  of 
soap  are  used.  These  amounts  vary  according  to  the 
hardness  of  the  water  and  the  condition  of  the  clothes. 
The  entire  process  in  the  wheel,  which  is  constantly 
in  motion,  lasts  about  half  an  hour,  but  the  cold  water 
bath  is  over  in  fifteen  minutes.  The  object  of  the 
cold  bath  is  to  remove  the  albumen  which  coagulates 
and  hardens  in  the  heat.  This  water  is  discharged  and 
the  clothes  are  rinsed.  Then  follows  a  run  in  hot  water 
and  soap,  150  to  180°  Fahrenheit  (65-80°  C.),  enough 
soap  being  used  to  make  a  good  suds.  Here  again  we 
observe  the  need  of  using  soft  water,  because  whatever 
measure  of  hardness  there  is  in  the  water  will  destroy 
the  corresponding  amount  of  soap  by  making  it  in- 
soluble. If  the  run  is  on  collars  and  shirts,  a  little 
bleach,  preferably  hypochlorite  of  soda,  is  put  in 
about  ten  minutes  before  the  end.  The  goods  then 
receive  three  successive  rinses,  about  five  minutes 
each,  and  then  comes  the  blue  solution,  usually 
aniline  blue  and  sometimes  ultramarine,  lukewarm, 
for  about  ten  minutes.  There  is  likely  to  remain  a 
little  alkali  at  this  time  which  tends  to  give  the 
clothes  a  grayish  tinge,  which  is  overcome  by  a  lit- 
tle acetic  or  oxalic  acid,  which  the  laundryman  calls 
his  "sour."  This  neutralizes  the  alkali  and  brings 
out  the  blue.  Then  follow  two  or  three  rinsings  in 
warm  or  cold  water  and  the  whole  lot  is  put  into  the 
centrifuge. 

Starched  goods  are  dried  and  dampened  before 
ironing,  while  underwear  and  such  goods  as  should 

280 


FATS,  OILS,  AND  THEIR  PRODUCTS 

be  very  soft  and  flexible  are  dried  in  a  rotary  dryer 
with  hot  air  passing  through. 

Home  washing  has  the  advantage  that  the  clothes 
receive  selective  treatment;  goods  are  washed  until 
they  are  clean  and  no  longer. 

Commercial  laundries  make  some  selection  between 
the  very  dirty  and  the  moderately  dirty  goods,  but  the 
selection  is  not  exact.  Whatever  is  put  into  a  lot  goes 
through  with  the  lot,  whether  it  needs  so  much  washing 
or  not.  On  the  other  hand,  the  laundry  wheel  does 
not  give  clothes  such  rough  treatment  as  a  washing- 
board.  Scientific  laundrymen  are  much  more  con- 
scientious as  to  the  materials  they  use  than  is  the 
casual  laundress. 

The  improvements  made  in  the  art  of  washing 
clothes  and  cloth  as  the  result  of  chemical  research, 
especially  at  the  Mellon  Institute  of  the  University 
of  Pittsburgh,  have  done  away  in  good  laundries  with 
the  practice  of  using  lye  and  bleaching-powder,  have  re- 
duced the  amount  of  bleach  and  acid  used  in  very  large 
measure,  and  the  present  work  is  toward  discover- 
ing the  real  action  of  soap  solutions  and  their  effects 
upon  fibers,  the  action  of  plain  water  and  of  mechan- 
ical processes.  When  the  best  results  are  discovered 
the  methods  will  be  standardized.  Many  foolish 
preparations  sold  under  fancy  names  and  labels  at  high 
prices  have  been  analyzed  and  proved  to  be  mere 
catchpenny  devices. 


XXIII 

SUGARS,  STARCH   AND  GUMS 

The  Steps  from  Paraffins  to  Sugars — The  Many  Different  Sugars — 
The  Study  of  Them — Emil  Fischer  and  Van't  Hoff — Making 
Cane  or  Beet  Sugar — Sucrose  and  Glucose — Candy — Chewing- 
gum — Gums  and  Varnishes — Varnishes  and  Paints — A  World 
Full  of  Troubles 

ET  us  go  back  to  the  paraffins  and  recall  those 
chains  of  hydrocarbons  in  which  the  carbon  atoms 
are  linked  together  by  one  bond,  and  the  other  affini- 
ties satisfied  with  hydrogen.  Methane,  CH4,  is  the 
first  of  the  series;  ethane,  C2H6,  is  the  next;  and 
so  on.  Then  the  alcohols  are  produced  by  the  sub- 
stitution of  an  OH  group  for  a  hydrogen  atom,  and 
you  may  remember  that  a  carbon  atom  does  not  like 
to  carry  more  than  one  OH  group.  Then,  recalling 
the  note  on  glycerin,  let  us  repeat  the  formula  given 
to  explain  it : 

Cmfi4  CH*OH  Nothing  more  here  in  the 

Methane      Methyl  Alcohol      OH  line,  only  one  C  atom 

C=Hy  C2HSOH  C-0*H    C-OH 

C=H3  EthylAlcohol  £*QH     C—H 

Ethane  Jtt       I  ^OH 

Glycol      C-OH 

Cj/id  C3H7OH  \72 

Propane  Propyl  Alcohol         Clycerol  or  Glycerin  - 

In  other  words,  as  we  fill  up  the  places  of  hydrogen 
with  OH  radicals  we  get  compounds  that  are  sweet 

282 


SUGARS,  STARCH  AND  GUMS 

and  sticky.    Now  let  us  make  longer  chains  and  we 
have: 


r$ 

^  H 

Glucose.Dextrose*  FrucLe.Levulost 

or  Grape  Sufar  or  Fruit  Sugar 

Roughly  speaking,  then,  a  sugar  is  an  aliphatic 
chain  having  many  OH  radicals  and  one  or  more 
CH2OH  or  CO  groups  in  the  molecule.  Sugars  with  the 
-H 

group  belong  to  the  aldehyde  bodies  and  are 

called  aldoses.  Those  with  the  CO  group,  on  ac- 
count of  their  relation  to  ketones,  are  called  ketoses. 
Such  are  all  simple  sugars.  "Ose"  is  the  termina- 
tion of  the  chemical  names  of  all  sugars.  A  simple 
sugar  is  a  sugar  of  one  chain  of  carbon  atoms,  and  they 
are  called  monosaccharides.  Now  let  us  imagine  two 
simple  sugars  joined  together  with  the  loss  of  water 
(H2O),  which  is  called  dehydration,  and  then  we  should 
have  a  sugar  composed  of  two  chains,  which  would 
be  called  a  disaccharide.  Here  we  are  getting  back  to 
familiar  ground  again,  for  sucrose  is  none  other  than 
cane  or  beet  sugar,  the  sugar  of  the  household,  the 
substance  of  the  lump  that  goes  into  the  cup  of  coffee. 
Observe,  then,  please,  that  sucrose  is  a  disaccharide 
composed  of  glucose  and  fructose,  less  one  molecule 
of  water. 

283 


EVERYMAN'S    CHEMISTRY 

Maltose  is  a  disaccharide  composed  of  two  glucose 
molecules  joined. 

Milk  sugar  is  a  disaccharide  composed  of  glucose 
and  galactose,  all,  of  course,  less  one  molecule  of 
water. 

Now  if  we  join  three  simple  sugars  together  we  have 
trisaccharides.  Thus,  raffinose,  an  impurity  of  cane- 
sugar,  is  a  trisaccharide.  Just  as  the  lower  members 
are  not  exactly  sugars,  but  rather  glycol  and  glycerol 
or  glycerin,  so  the  higher  members  beyond  which 
these  chains  of  glucose,  fructose,  etc.,  are  combined  as 
polysaccharides,  many  in  one  molecule,  cease  to  be 
sugars  but  get  to  be  starches  and  gums.  And  further 
on,  with  still  more  chains  of  these  simple  sugars  all 
polymerized  into  molecules  as  big  as  your  fist,  if  you 
undertake  to  write  them  down  and  really  know  their 
constitution,  and  your  writing  is  not  too  fine,  we 
have  cellulose !  That  is  the  reason  why  alcohol  may  be 
made  from  sawdust.  The  whole  list  is  known  as  carbo- 
hydrates. 

,  It  would  seem,  then,  that  it  would  be  an  easy  task 
to  make  any  sugar  we  want;  that  if  we  have  glucose 
and  fructose  we  could  "just  take  and  go  to  work" 
and  dehydrate  them  and  there  we  should  have  all 
the  table  sugar  we  want  made  out  of  corn  and  pump- 
kins. But  here  we  come  to  a  difficulty  again.  By  the 
action  of  acids  the  polysaccharides  are  easily  broken 
up  into  simple  sugars;  that  is  easy  and  is  the  basis 
of  the  glucose  industry.  But  the  other  way  about, 
the  locking  up  of  simple  sugars  into  the  more  complex 
bodies,  is  a  trick  that  nature  knows  but  that  we  haven't 
learned  yet.  All  of  these  carbohydrates  are  made  by 
nature  out  of  carbon  dioxide  and  water — sugars, 
starches,  gums,  and  cellulose.  Two  monosaccharides 
have  been  dehydrated  to  a  disaccharide,  but  only  with 

284 


SUGARS,  STARCH  AND  GUMS 

great  pains  and  circumstance.  And  even  then  it  did 
not  turn  out  as  it  was  expected  to. 

The  history  of  the  study  of  sugars  is  interesting. 
They  are  all  sweet  and  soluble  and  gummy.  Both 
acids  and  alkalies  break  them  down  so  effectively  that 
their  structure  is  lost  in  the  operation,  and  so  the  work 
on  sugars  was  formerly  very  indefinite.  Then  the  prob- 
lem was  to  get  some  crystalline  derivative  of  the 
sugars  that  was  distinctly  marked  in  each  case.  In 
1887  Emil  Fischer  discovered  this:  he  found  that 
phenylhydrazine  in  the  presence  of  acetic  acid  makes 
with  sugars  beautiful,  moderately  soluble  crystals 
which  are  called  osazones,  that  every  sugar  has  its 
own  distinct  characteristics,  and  that  by  this  means 
the  different  sugars  may  be  recognized.  Just  consider 
the  patience  it  must  have  taken  to  discover  this! 
He  had  been  working  for  years  on  the  subject. 

But  that  was  not  enough.  The  osazones  showed 
that  there  were  a  great  many  kinds  of  sugars,  but 
what  were  they?  The  proportions  of  carbon,  hydro- 
gen, and  oxygen  in  the  molecule  are  the  same  in  many 
different  kinds — the  many  isomeric  sugars  that  are 
the  same  in  composition  and  yet  different  in  the  rela- 
tive positions  occupied  by  the  atoms  within  the  mole- 
cules. So  we  must  consider  the  work  of  Jacobus 
Henricus  van't  Hoff,  a  young  Dutch  chemist  from 
Delft.  He  studied  in  Paris  and  in  Bonn.  As  a  student 
he  was  more  of  a  dreamer  than  a  chemist;  he  had  a 
philosophical  turn  of  mind  and  a  head  for  mathe- 
matics. His  avocation  was  the  study  of  Byron,  and 
he  caused  somewhat  of  a  flutter  in  the  dove-cotes  by 
writing  very  pretty  poems  in  English  to  the  attractive 
girls  that  he  met.  When  he  came  to  Bonn,  where 
Professor  Kekule  at  that  time  was  teaching,  and  had 
worked  out  the  formula  for  the  benzol  ring,  he 

285 


EVERYMAN'S    CHEMISTRY 

was  curious  to  know  where  those  carbon  bonds  were. 
If  that  benzol  molecule  was  a  thing,  what  shape  was 
it?  If  there  were  those  four  bonds  attached  to  each 
carbon  atom,  which  way  did  they  reach  out?  That 
an  atom  is  almost  infinitely  small  did  not  disturb 
his  mathematical  mind  in  the  least.  The  great  Kekule 
did  not  help  him,  neither  did  anybody  else,  so  he 
proceeded  to  work  out  the  study  of  stereochemistry, 
or  place-chemistry,  which,  as  we  have  said,  we  shall 
not  develop  in  this  work.  Suffice  it  to  say  that  van't 
HofT  worked  out  his  theories  and  published  them 
against  angry  and  scornful  opposition.  He  had  re- 
turned to  Holland  by  this  time  and  was  lecturing  in 
a  veterinary  college  in  Amsterdam,  and  "the  Dutch 
horse-doctor"  was  assured  that  he  was  an  ignoramus 
and  everything  else  undesirable.  But  van't  Hoff 
bided  his  time.  He  had  faith.  Finally  the  great 
Emil  Fischer  applied  the  work  of  van't  Hoff  to  his 
sugars.  He  found,  according  to  stereochemistry,  that 
there  were  sixteen  different  kinds  of  glucose  possible. 
By  1893  he  had  made  eleven  of  them,  and  now  they 
have  all  been  produced.  Without  stereochemistry  the 
knowledge  of  these  things  would  have  been  impos- 
sible. Since  then  the  study  of  sugars  has  been  carried 
on  by  Nef  and  others,  and  the  subject  constitutes  one 
of  the  most  thoroughly  studied  branches  of  organic 
chemistry. 

Cane-sugar,  or  sucrose,  is  found  in  sugar-cane,  in 
beets,  sorghum,  sugar-maple  sap,  and  honey.  At  one 
time  great  hopes  were  entertained  of  making  sugar 
from  sorghum,  but  the  beet-sugar  industry  has  taken 
its  place.  The  tropical  sugar-cane  is  harvested  and 
the  cane  is  cut  or  lacerated,  and  then  run  through 
heavy  rollers  to  squeeze  out  the  juice.  The  beets  are 
cut  into  long,  thin  slices  in  order  to  break  up  the 

286 


SUGARS,  STARCH  AND  GUMS 

membranes  of  the  cells  which  contain  the  sugar. 
These  are  placed  in  vats  through  which  water  circu- 
lates, the  nearly  exhausted  material  being  acted  on 
by  fresh  water  while  the  material  richest  in  sugar  is 
treated  with  the  strongest  solution,  with  a  view  to 
using  the  least  amount  of  water  possible  in  the  process. 
The  result  is  a  solution  of  12  to  15  per  cent,  of  sugar, 
which  is  about  the  proportion  contained  in  the  beet 
itself. 

A  greatly  desired  invention  would  be  the  ability  to 
dry  these  slivers  of  sugar-beets  so  that  they  might  be 
stored  and  transported,  to  avoid  the  necessity  of 
extracting  the  sugar  where  the  beets  are  grown.  As 
it  is,  the  beets  are  harvested,  cut  up,  and  the  raw 
sugar  extracted  in  a  factory  located  in  the  beet  dis- 
tricts of  Michigan,  Colorado,  California,  or  wherever 
else  they  may  grow.  The  season  is  hardly  over  two 
months  long  and  the  expensive  factories  remain  idle 
for  the  other  ten  months  every  year.  This  is  bad 
practice  and  far  from  economical.  A  great  saving 
would  be  made  if  the  factories  could  be  centrally  lo- 
cated and  operated  all  the  year  through,  and  as  soon 
as  the  drying  methods  are  perfected  this  should  be 
possible.  Many  have  tried  to  do  this,  but  without 
success.  I  am  informed,  however,  that  the  art  has 
been  achieved,  although  it  has  not  been  brought  into 
general  practice  as  yet.  The  same  holds  true  of  cane- 
sugar,  and  I  understand  the  plan  is  worked  out  and 
in  operation  on  a  small  scale  to  dry  the  sugar-cane  on 
the  plantations,  bale  it,  and  ship  it  to  temperate  cli- 
mates, and  there  have  the  sugar  extracted  from  the 
cane  all  the  year  round,  while  the  spent  cane  is  then 
used  for  making  paper. 

The  treatment  of  the  beet-sugar  solution  is  very 
similar  to  that  of  the  juice  of  sugar-cane.  Slacked 

28? 


EVERYMAN'S    CHEMISTRY 

lime  is  added  to  neutralize  and  precipitate  the  organic 
acids  that  are  present,  along  with  the  phosphates. 
This  is  very  necessary,  because  the  presence  of  the 
acids  in  solution  would  decompose  or  " crack"  the 
sucrose  to  glucose  and  fructose,  which  are  not  wanted 
at  all.  The  lime  also  precipitates  the  nitrogenous 
bodies  or  proteins  and  some  of  the  coloring-matter. 
Then  it  is  run  through  a  filter  press  to  get  rid  of  the 
lime  precipitate  and,  because  sugar  does  not  crystal- 
lize out  well  if  heated  to  a  high  temperature,  the  solu- 
tion of  sugar  and  water  is  boiled  down  in  vacuum  pans. 
As  you  reduce  the  air  pressure,  the  boiling-point  is 
reduced.  Carbon  dioxide  is  run  through  the  syrup 
to  get  out  the  lime  that  remains  in  solution,  and  after 
filtration  the  syrup  is  still  further  concentrated  until 
crystals  begin  to  appear.  Then  it  is  cooled  and  the 
brown  sugar  crystallized  out.  This  is  separated  in  a 
centrifugal  machine  and  the  molasses,  which  will  not 
crystallize — is  molasses.  The  molasses,  except  that 
which  covers  buckwheat  cakes  and  goes  into  ginger- 
bread and  candy,  is  sold  for  the  production  of  alcohol. 
Most  of  the  denatured  alcohol  made  in  the  United 
States  at  present  is  the  product  of  molasses. 

Thus  we  have  brown,  or  raw,  sugar.  It  is  dissolved 
again  and  filtered  through  bone-black  to  remove  the 
coloring-matter.  The  filtered  solution  is  then  concen- 
trated once  more  in  vacuum  pans  and  run  into  tanks, 
in  which  it  crystallizes  out  in  the  form  of  granulated 
sugar,  the  sugar  of  commerce.  It  still  has  a  brownish 
or  yellowish  tinge,  and  we  users  of  sugar  in  our  coffee 
and  tea  want  the  product  perfectly  pure,  or,  in  other 
words,  pure  white.  Now  we  can  crystallize  sugar 
again  and  again  and  it  will  still  have  a  little  yellowish 
tinge,  because  that  is  its  natural  color.  So  Mr. 
Refiner  meets  the  situation  by  putting  a  little  blue 

288 


SUGARS,    STARCH    AND    GUMS 

coloring-matter  into  the  solution,  which  neutralizes  its 
yellowish  tint.  He  uses  ultramarine,  which  does  us 
no  harm.  Then  the  sugar  has  a  beautiful  bluish  white 
color  which  satisfies  us  and  satisfies  him  and  enables 
the  grocer  to  make  a  profit  on  his  high-grade  wares. 

Sucrose,  or  cane-sugar,  melts  at  160°  centigrade. 
When  kept  at  its  melting-point  for  a  time  and  then 
allowed  to  cool  it  solidifies  into  an  amber-colored 
mass  that  is  called  in  England  "barley-sugar,"  be- 
cause barley-water  was  at  one  time  generally  used  in 
its  preparation.  In  the  United  States  it  is  more  likely 
to  be  called  "stick  candy,"  or,  going  back  a  genera- 
tion, "Jackson  balls."  When  cane-sugar  is  boiled 
with  dilute  acids  and  so  is  split  into  dextrose  and  levu- 
lose  it  will  not  crystallize  readily.  That  is  the  reason 
why  a  little  vinegar  (acetic  acid)  is  added  to  candy 
that  is  to  be  pulled. 

Candy. — The  making  of  candy  is  an  industry  based 
in  part  on  the  fact  that  sugar  becomes  "barley-sugar" 
and  is  amorphous  and  glass-like  when  heated  to  160° 
centigrade.  When  it  is  heated  to  210°  centigrade 
it  loses  water  and  becomes  caramel.  It  is  :an  im- 
portant industry  when  we  consider  the  vast  amounts 
that  are  exported  to  tropical  countries.  The  greatest 
amount  is  made  in  the  form  of  hard  candies,  which 
are  70  per  cent,  glucose  and  the  rest  sucrose  and 
water.  Now  let  us  stop  right  here  and  fuss  and  fume 
a  little  over  the  good  people  who  fear  glucose  because 
it  is  "a  chemical  product."  Let  us  see  how  much  more 
of  a  chemical  glucose  is  than  cane-sugar.  The  glucose 
is  made  from  corn  and  the  solution  is  treated  with  a 
mild  acid  to  split  off  the  simple  sugar  from  the  starch. 
The  cane-sugar  is  extracted  from  cane  or  beets  and  the 
solution  treated  with  an  alkali  to  remove  the  organic 
acids.  This  is  the  chief  difference  in  the  processes, 

289 


EVERYMAN'S   CHEMISTRY 

and  if,  so  far  as  manufacture  goes,  glucose  is  a  danger- 
ous chemical  while  sucrose  or  cane-sugar  is  not,  then 
we  might  as  well  come  to  the  conclusion  that  caustic 
lime  is  edible  while  vinegar  is  a  poison.  After  that, 
the  processes  are  somewhat  similar  except  that  there 
is  no  artificial  coloring-matter  in  glucose  when  it  comes 
upon  the  market,  whereas  there  is  an  infinitesimal 
amount  in  sucrose,  or  sugar.  The  absurd  value  of  the 
advertising  slogan  "no  chemicals  used"  is  not  a  favor- 
able comment  on  our  intelligence.  It  is  only  one  step 
in  advance  of  the  old  patent-medicine  advertisements 
that  were  assured  to  be  harmless  because  they  were 
"purely  vegetable"  —  and  so  contained  nothing 
stronger  than  40  per  cent,  of  alcohol,  or  a  little  mor- 
phine, strychnine,  belladonna,  and  such  other  "purely 
vegetable"  simples.  The  superstition  that  anything 
with  a  chemical  name  is  dangerous  to  health  is  based 
on  crass  ignorance.  Glucose  is  just  as  healthy  as 
sucrose.  Years  and  years  of  human  experience  and 
physiological  experimentation  prove  this. 

To  return  to  hard  candies,  the  mixture  of  glucose, 
sucrose,  and  water  is  heated  in  open  steam- jacketed 
kettles  and  then  boiled  down  in  vacuum  pans  to  pre- 
vent the  formation  of  caramel,  while  the  excess  water 
is  removed.  Here  the  flavor  and  coloring-matter  are 
put  in  at  the  end  of  the  process.  Then  it  is  run  into 
flat  pans  on  a  table,  layers  of  different  colors  are  im- 
posed one  upon  another,  and  it  is  drawn  or  rolled  up 
and  worked  into  the  forms  and  shapes  that  are 
wanted. 

Gum  goods  are  chiefly  glucose  and  water  with  very 
little  cane-sugar.  Gum-drops  may  contain  a  little 
gum-arabic,  and  are  molded,  dried,  put  in  a  pan,  and 
covered  with  a  crystallizing  syrup  which  is  a  solution 
of  about  50  per  cent,  sucrose  in  water.  The  syrup 

290 


SUGARS,    STARCH   AND   GUMS 

is  drained  off  and  sugar  crystals  form  on  the  outside  of 
the  gum-drops. 

Peanut-brittle  is  glucose  and  cane-sugar  heated 
until  the  point  is  reached  where  it  begins  to  caramel. 
Then  the  peanuts  are  added.  Some  makers  add 
roasted  peanuts  and  some  prefer  unroasted  nuts.  The 
syrup  is  so  hot  that  it  cooks  them,  anyway.  Then 
the  mixture  is  poured  upon  marble  slabs  and  allowed 
to  cool. 

Chocolate  cream-drops. — The  "cream,"  or  inside,  is 
cane  or  beet  sugar,  for  they  are  the  same,  and  water 
heated  together  into  a  creamy  consistency,  and  then 
it  is  molded  and  dried.  The  chocolate  coating  con- 
tains about  65  per  cent,  cane-sugar  and  about  32  per 
cent,  cocoa.  To  get  the  right  consistency,  cocoa 
butter  is  added  and  then  the  candy  is  dipped.  Ma- 
chine-dipped candy  goes  through  much  faster  than 
that  dipped  by  hand,  and  so  the  coating  is  thinner. 
Too  much  of  the  coating  would  stick  to  the  machine 
if  it  were  operated  slowly  enough  to  make  a  thick  cov- 
ering. There  is  considerable  art  in  making  a  good 
chocolate  coating.  It  should  have  a  good  cracking 
quality  and  break  with  a  snap.  If  it  is  not  well  made 
it  lacks  this  quality.  The  dipping  mass  is  better  if 
it  is  made  and  cooled  and  allowed  to  stand  for  a  few 
days  and  then  melted  for  the  dipping  process.  The 
temperature  must  also  be  guarded  carefully,  because 
if  the  mass  is  too  hot  the  covering  becomes  streaky. 

Chocolate  is  made  by  roasting  cocoa  beans  and 
pressing  out  some  of  the  oil  which  is  known  as  cocoa 
butter.  What  is  known  as  bitter  chocolate,  or  the 
chocolate  sold  for  cooking  purposes,  contains  about 
50  per  cent,  of  the  cocoa  oil  or  butter.  The  (adjective 
deleted  by  publisher)  stuff  known  as  cocoa  powder 
or  breakfast-cocoa  is  the  pulp  of  the  cocoa  beans  with 

291 


EVERYMAN'S    CHEMISTRY 

nearly  all  the  oil  pressed  out.  It  is,  I  believe,  entirely 
wholesome  to  drink  and  eat  in  quantity. 

Cheap  candies  are  just  as  wholesome  as  the  expen- 
sive product.  The  principal  difference  is  that  the  one 
is  worked  by  machinery,  whereas  the  other  is  worked 
by  hand,  and  the  chocolate  coverings  are  much  thicker 
in  the  more  expensive  kinds.  Poisonous  dyes  are  not 
used  in  coloring  them;  but  even  if  those  of  question- 
able effect  were  employed,  cases  of  poisoning  would 
be  more  likely  to  occur  as  a  result  of  taking  too  much 
sugar  than  from  the  pigment.  The  amount  of  pigment 
employed  is  very,  very  slight. 

Chewing-gum. — Why  Americans  chew  gum  is  a  fair 
question  to  bring  up  before  a  debating  society.  It  is 
said  that  some  200,000,000  people  chew  betel-nut, 
but  they  are  not  of  the  Indo-European  races  to  which 
we  belong.  Europeans  do  not  seem  to  take  to  gum, 
although  there  is  a  rumor  to  the  effect  that  the 
long,  silent  watches  in  the  trenches  have  started  the 
habit  among  many  soldiers.  For  the  exercise  of  the 
great  American  jaw  no  less  than  7,000,000  pounds 
of  chicle  are  imported  annually  into  the  United 
States. 

Spruce  gum  was  the  secret  joy  of  our  childhood, 
although  the  amount  produced  was  not  large.  An 
apothecary  named  Colgan,  of  Louisville,  Kentucky, 
made  spruce  gum  and  found  a  considerable  market  for 
his  product.  He  read  in  one  of  his  trade  papers  that  a 
large  consignment  of  a  gum  called  chicle  made  of  the 
sap  of  the  sapota  tree  had  arrived  in  New  York  and 
that  the  consignees  were  trying  to  find  a  market  for 
it.  It  had  been  hoped  that  it  would  serve  as  a  sub- 
stitute for  caoutchouc,  but  this  was  not  successful.  So 
the  Louisville  man  sent  for  a  sample  order,  tried  it 
out,  found  that  it  succeeded,  and  speculated  on  all, 

292 


SUGARS,  STARCH  AND  GUMS 

or  nearly  all,  of  the  cargo  with  signal  success.    So  the 
great  jaw- wagging  began. 

Chicle  is  related  to  the  rubbers,  and  some  of  its 
constituents  are  the  same.  The  gum-makers  melt  it 
in  kettles  to  destroy  the  fibers  and  eliminate  the 
water,  although  they  do  not  heat  to  a  high  tempera- 
ture. It  should  then  be  filtered  to  clean  it,  although 
this  is  not  always  done.  Then  glucose  is  added  until 
it  reaches  the  proper  consistency,  and  cane-sugar  and 
flavoring  are  stirred  in  until  thoroughly  mixed.  It  is 
then  taken  out  of  the  kettle  and  kneaded  into  cakes 
of  about  twenty  pounds  each  and  run  through  sizing- 
rolls  to  bring  it  into  sheets  of  the  desired  thickness. 
Then  it  is  run  through  scoring-rolls  which  mark  out 
each  piece.  Then  it  is  cooled,  broken  into  the  pieces 
marked  by  the  scoring  -  rolls,  and  wrapped  and 
marketed. 

Cheaper  gums  are  made  in  whole  or  part  of  deres- 
inified  Pontianak  rubber,  and  in  some  it  is  possible 
that  rubber  resins  are  used.  What  is  needed  in  the 
industry  is  to  provide  that  the  gums  remain  soft  in 
cold  weather  and  to  prevent  them  from  growing 
brittle  with  age. 

Gums  and  Varnishes. — Gums  are  mostly  high  sugars 
— polymerized  sugars  with  molecules  of  a  great  many 
atoms.  The  more  frequently  found  and  consequently 
cheaper  ones  have  an  acid  reaction  which  may  come 
from  impurities.  They  are  built  up  within  the  tree 
or  plant,  which,  within  its  remarkable  chemical  works, 
brings  water  and  carbon  dioxide  into  combination  as 
sugars,  and  bunches  the  sugars  into  gums  and  starch 
and  into  cellulose  for  the  walls  of  its  cells. 

Of  course  these  gums  are  legion  in  number.  The 
cheapest  of  all  is  rosin,  and  some  of  the  most  expensive 
ones  are  fossilized,  the  latter  making  excellent  var- 

293 


EVERYMAN'S    CHEMISTRY 

nishes,  but  usually  hard  to  dissolve,  and  a  good  part 
of  them — about  16  per  cent,  in  practice — is  lost  by 
heat  when  they  are  dissolved  in  oils. 

The  business  of  a  varnish  is  to  make  a  covering  for 
objects  as  though  it  were  covered  with  liquid  glass. 
Paint  does  similar  work  except  that  the  covering  is 
opaque,  and  the  differences  between  paint  and  varnish 
are  not  very  clearly  drawn;  especially  since  varnishes 
that  are  to  stand  the  weather  are  often  loaded  up  with 
finely  divided  lampblack  or  other  pigment.  But  we 
need  not  bother  about  that.  For  the  present  we  have 
to  do  with  varnishes  made  of  gums  of  one  sort  or  an- 
other which  we  desire  to  dissolve  and  apply. 

Rosin  will  not  do  alone  for  varnish,  because  it  is 
too  soft;  it  has  no  lasting  qualities;  nevertheless,  it 
is  used  in  some  varnishes.  Shellac,  from  the  lac  tree, 
is  often  used  in  spirit  varnishes  for  inside  work,  but 
it  is  not  an  ideal  covering,  either,  because  it  is  too 
waxy.  There  are  trade  troubles  about  it,  too.  It  is 
graded  according  to  color,  which  means  that  it  is 
submitted  to  all  sorts  of  chemical  bleaching  agents 
which  often  play  hob  with  its  chemical  structure. 
General  tests  of  shellac  will  show  not  less  than  5 
per  cent,  of  rosin  and  vast  amounts  of  rosin  are  ex- 
ported from  Savannah  to  East  India  only  to  be 
brought  back  mixed  with  shellac.  The  best  of  all  gums 
for  varnish  are  copal  and  fossil  resins  dissolved  with 
good  petroleum  benzine  and  mixed  with  cold,  pressed 
linseed-oil. 

There  are  two  kinds  of  varnish — spirit  and  oil. 
Spirit  varnish  is  usually  shellac  dissolved  in  alcohol, 
and  is  good  for  inside  work.  The  point  with  spirit 
varnishes  is  to  get  the  coat  on  and  have  it  ready  for 
almost  immediate  use,  and  when  the  varnish  is  once 
applied  we  have  no  further  use  for  the  solvent;  we 

294 


SUGARS,  STARCH  AND  GUMS 

want  it  to  hie  away  as  quickly  as  possible  and  not 
remain  as  a  boarder.  For  this  purpose  many  different 
kinds  of  solvents  are  used.  There  are  grain  alcohol 
and  wood  alcohol,  acetone — which  makes  the  varnish 
thicken  too  fast — and  turpentine  and  petroleum  ben- 
zine, as  well  as  others.  The  automobile  business  has 
spoiled  the  quality  of  petroleum  benzine  as  we  have 
already  noted,  because  instead  of  providing  a  series 
of  light  hydrocarbons  they  now  sell  a  body  of  the 
same  specific  gravity  but  composed  of  still  lighter 
petroleums,  together  with  those  much  heavier.  A 
petroleum  benzine  supposed  to  boil  at  from  70°  to 
120°  centigrade  will  contain  bodies  that  distil  over  at 
from  120°  to  200°  centigrade,  and  by  the  time  varnish 
dissolved  in  that  kind  of  solvent  is  thoroughly  dry 
your  patience  is  likely  to  be  lost  and  your  temper  in 
trouble. 

Fat  or  oil  varnishes  are  mixed  with  an  oil  which 
leaves  are  sidue  that  dries  slowly  as  it  oxidizes.  To 
assist  in  this  process,  "driers"  are  put  in,  which  are 
oxidizing  agents,  such  as  lead  oxide  or  manganese 
dioxide.  The  action  is  not  simple  at  all. 

Linseed-oil  is  about  the  best,  but  the  merits  of  others 
are  urged.  Formerly  linseed-oil  was  pressed  cold,  which 
produced  a  splendid  product,  but  the  yield  was  small. 
Now  in  order  to  improve  the  yield  in  bad  years  it  is 
pressed  hot,  and  that  brings  with  it  foots  and  al- 
buminous substances,  mucilage,  plant  tissue,  and  all 
sorts  of  things  that  are  not  wanted.  The  supply  of 
flaxseed  is  subject  to  great  variations,  being  large 
one  year  and  small  the  next,  so  while  the  demand 
is  steady,  the  rule  that  "the  higher  the  price  the 
lower  the  quality"  may  nearly  be  said  to  hold  good. 
The  Dutch  artists  of  Rembrandt's  time  who  made 
their  own  pigments  were  very  particular  in  regard  to 
20  295 


EVERYMAN'S    CHEMISTRY 

their  linseed-oil,  allowing  it  to  stand  many  years  in 
order  to  get  thoroughly  clear.  Our  current  methods 
of  the  purchase  and  sale  of  package  goods  has  resulted 
in  unfortunate  ignorance  on  the  part  of  the  artists  of 
to-day  of  the  materials  they  use.  Sir  Joshua  Reynolds 
and  his  colleagues  were  great  hands  at  trying  experi- 
ments, and  their  pictures  tell  the  story. 

China-wood  or  Tung  oil  is  an  excellent  product  of 
great  elasticity,  but  it  is  hard  to  dry.  It  has  a  re- 
markable trick  of  jellifying  after  it  has  been  heated 
and  growing  insoluble  so  that  it  cannot  be  cut.  Its 
difficulties,  however,  are  being  mastered.  Soya-bean 
oil  in  regard  to  a  medium  for  paints  and  varnishes  is 
less  understood  than  linseed  or  Tung.  It  is  also  hard 
to  dry.  Cotton-seed  oil  and  corn-oil  are  often  mixed 
with  linseed.  They  have  their  uses.  Generally  speak- 
ing, the  ultimate  use  determines  how  varnishes  should 
be  made,  although  a  lot  of  the  chemistry  of  the  art  is 
still  unknown. 

Spar  varnish  was  originally  intended  for  the  wooden 
spars  of  ships,  and  it  is  a  covering  designed  to  stand 
the  worst  kind  of  weather  conditions.  It  is  usually  a 
slow-drying  oil  varnish  with  good  hard  gum.  China- 
wood  oil  is  generally  used  in  spar  varnishes. 

As  an  instance  of  the  need  of  varnishes  and  paints, 
steel  begins  to  decay  as  soon  as  it  leaves  the  rolls. 
Air,  moisture,  and  sulphur  fumes  bring  this  about, 
so  it  needs  to  be  covered  as  soon  as  possible.  The  final 
covering  should  be  with  three  coats,  and  it  is  well  to 
have  them  of  different  colors  so  as  to  be  sure  all  three 
coats  have  been  put  on.  Painters,  like  other  men,  have 
been  known  to  skip  work  sometimes,  and  if  the  same 
color  is  used  this  will  not  show.  But  as  the  pigments 
are  likely  to  be  different  metallic  oxides  or  salts,  there 
is  also  the  danger  that  with  different  colored  paints 

296 


SUGARS,   STARCH   AND   GUMS 

electrolytic  action  may  set  up  between  the  different 
metals  and  thus  hasten  the  decay  of  the  steel.  This 
world  is  certainly  full  of  troubles  and  we  need  chemical 
advice  at  every  step ! 

Starch. — These  carbohydrates,  including  the  sweet, 
gummy  products  ranging  from  glycerin  to  the  most 
complex  sugars,  have  ways  of  bunching  up  their  mole- 
cules, sometimes  giving  up  water  and  sometimes  taking 
it  on,  and  forming  a  long  series  of  bodies  that  are  of 
enormous  importance  in  natural  processes,  but  there 
has  not  been  reached  a  sufficiently  clear  agreement  and 
understanding  on  the  subject  to  bring  it  into  popular 
discussion.  The  trained  organic  chemist,  too,  can  see 
these  molecules  in  his  mind's  eye;  can  be  convinced 
at  which  point  each  atom  or  radical  is  placed,  while 
we  have  not  wandered  sufficiently  far  in  this  book  to 
make  that  problem  easy.  So  we  shall  only  consider 
the  subject  superficially. 

We  know  that  dextrose,  a  simple  sugar,  is  easily 
converted  into  dextrine,  and  dextrine,  with  water,  is 
a  gummy  substance.  Now  starch,  which  is  (CeHioC^x 
— that  is,  C6Hi0O5  multiplied  by  an  indefinite  number — 
is  converted  by  heat  into  dextrine,  and  the  hot  iron 
of  the  laundries  does  this  to  the  starch  on  linen, 
covering  the  fibers  with  a  hardened  gum.  But  the 
laundry,  while  the  most  familiar,  is  in  effect  the  least 
use  for  starch.  It  is  the  great  assimilation  product  of 
plants.  The  seeds  contain  it,  and  this  feeds  the  young 
plant  until  it  grows  big  enough  to  make  the  carbo- 
hydrates— that  is,  the  sugars  and  gums  as  well  as 
starch  and  cellulose  which  it  needs  in  the  process  of 
living  and  growth,  from  water  and  carbon  dioxide  from 
the  air.  It  is  likely  that  the  plants  produce  sugars  of 
one  sort  or  another  first  and  then  bunch  the  molecules 
to  glims  and  starch.  We  find  starch  in  the  following 

297 


EVERYMAN'S    CHEMISTRY 

percentages  in  well-known  grains:  Winter  wheat, 
63.7;  spring  wheat,  65.8;  barley,  63.5;  English  oats, 
49.7;  corn,  64.6;  rye,  6 1. 8,  and  Carolina  rice  (husked), 
77.6.  We  must  have  starch  in  food  for  both  man 
and  beast,  as  well  as  for  plants.  We  cannot  build  up 
sugars  into  starch,  as  nature  does,  but  we  can  split 
them  down  to  simpler  substances — which  nature  does 
also.  For  instance,  dilute  acids  split  starch  down  to 
dextrine  and  then  to  dextrose  or  glucose.  Heat  does 
this  also.  In  the  presence  of  certain  ferments,  such  as 
saliva  or  the  diastase  of  malt,  starch  is  changed  to 
maltose. 

Starch  is  a  colloid,  not  exactly  soluble  in  cold  water, 
and  yet  in  hot  water  it  absorbs  so  much  that  it  swells 
up  into  a  pasty  mass.  This  is  why  rice  swells  up  so 
when  it  is  boiled.  It  dries  out  into  minute  granules  of 
different  sizes — from  0.004  to  0.0079  of  an  inch  in 
diameter — and  in  shape  according  to  its  origin.  Some 
granules  are  round,  some  oval,  and  some  truncated. 
Whether  prepared  from  corn  (maize) ,  as  in  the  United 
States,  or  potatoes,  as  in  Europe,  or  arrowroot,  as  in 
the  West  Indies,  the  process  consists  in  destroying  the 
cell  tissues,  usually  by  mechanical  means,  and  then 
washing  out  the  starch  and  drying  it  carefully.  By 
further  treatment  with  a  dilute  acid  and  by  heating 
it  is  converted  into  glucose,  or  grape  or  corn  sugar. 

There  is  another  polyose — now  you  remember  the 
chemical  names  of  all  the  sugars  end  in  ose,  so  starch 
is  a  polyose,  or  many-sugar — called  glycogen,  which 
is  found  in  animal  organisms  and  is  usually  prepared 
from  the  liver.  It  has  the  same  formula  as  starch, 
C6HioO5,  multiplied  we  do  not  know  how  many  times, 
and  this  is  a  white  powder  which  dissolves  in  water, 
giving  an  opalescent  solution.  And  these  glycogens 
show  differences  according  to  the  animal  from  which 

298 


SUGARS,    STARCH   AND    GUMS 

they  are  isolated.  For  instance,  horse  meat  may  be 
recognized  by  its  glycogen  content,  which  is  greater 
than  that  of  beef. 

The  baking  of  a  loaf  of  bread  is  a  very  interesting 
process,  and  recent  events  have  proved  that  it  is  well 
worth  the  chemist's  attention.  Flour  is  principally 
starch  in  one  of  its  many  forms,  with  some  sugars, 
and  then  some  other  bodies.  As  every  baker  knows, 
flour  is  tricky  stuff  and  full  of  ways  that  are  vain. 
There  is  great  room  for  chemical  research  in  the  milling 
industry,  and  in  baking  and  cooking,  too. 

The  ingredients  for  bread  are  flour  and  water,  yeast, 
salt,  fat,  sugar,  and  milk.  Yeast  is  a  member  of  a 
considerable  family  of  plants,  of  which  each  variety  has 
ways  of  its  own.  You  can  bake  bread  with  brewers' 
yeast,  but  distillers'  is  better,  and  specially  grown 
yeast  for  baking  is  better  still.  In  some  countries  it  is 
forbidden  to  use  brewers'  yeast  for  baking.  When  the 
dough  is  made  it  is  set  aside  in  a  warm  place  to  let 
the  yeast  grow,  and  as  this  microscopic  plant  proceeds 
to  do  so  it  produces,  as  it  matures,  two  bodies  which 
straightway  come  into  use.  The  first  changes  the 
sugar  that  is  within  the  wheat  and  that  which  has 
been  added  into  a  form  that  will  ferment.  The  second 
ferments  the  sugar — that  is,  it  splits  it  down  to  ethyl 
alcohol,  C2H5OH,  and  carbon  dioxide,  CO2.  Then  the 
bread  rises,  because  the  CO2  needs  room  for  itself  in 
that  solid  dough,  and  it  expands  wherever  it  is  formed 
in  all  parts  of  the  bread,  making  holes  for  itself  be- 
cause the  sticky  gluten  will  not  let  it  out.  The  baker 
or  the  housewife  looks  at  the  dough,  observes  that  it 
has  "raised,"  and  then  it  goes  into  the  oven. 

Here  it  meets  a  new  situation.  In  all  that  heat  the 
alcohol  is  quickly  turned  to  vapor,  and  it  wants  to 
escape.  So  does  the  carbonic-acid  gas.  In  this,  espe- 

299 


EVERYMAN'S    CHEMISTRY 

daily  the  alcohol  appears  to  succeed,  for  I  have  yet 
to  learn  of  anybody  who  was  made  drunk  by  eating 
bread.  On  the  outside  of  the  loaf  the  sugar,  by  means 
of  the  heat  and  the  air,  is  converted  into  caramel,  and 
so  the  crust  has  an  entirely  different  taste  from  that 
of  the  bread.  The  yeast  is  baked,  too,  but  that  does 
no  harm — it  has  finished  its  business. 

Now  let  us  see  how  chemical  research  enters  into  so 
familiar  a  process  as  bread-baking.  We  shall  consider 
two  improvements,  both  worked  out  in  the  Mellon 
Institute  of  Industrial  Research  of  the  University  of 
Pittsburgh  after  a  start  at  the  University  of  Kansas, 
and  both  by  the  same  man.  When  the  late  Robert 
Kennedy  Duncan  established  industrial  fellowships  at 
the  University  of  Kansas,  the  National  Association  of 
Master  Bakers  wanted  to  know  how  to  make  "salt- 
risin'  bread."  This  was  a  product  of  the  frontier, 
where  yeast  was  not  to  be  had.  Some  forgotten 
woman,  with  a  sense  of  the  reasons  why  things  happen, 
put  sour  milk  and  corn-meal  and  salt,  and  possibly 
something  else,  together  until  it  proceeded  to  ferment. 
This  she  mixed  in  the  dough  batch  instead  of  the  yeast 
which  she  did  not  have,  and  sometimes  the  result  was 
excellent  bread.  It  was  not  the  same  as  ordinary 
bread;  the  holes  were  smaller  and  there  were  more  of 
them.  Old  frontiersmen  often  cried  out  for  "salt- 
risin'  bread";  they  wanted  it  badly,  and  yet  no  one 
alive  could  be  sure  of  success  in  baking  it,  no  matter 
how  carefully  the  recipes  were  followed.  So  the 
bakers'  association  donated  a  fellowship,  and  Professor 
Duncan  put  Doctor  Kohman  at  work  at  it.  Some- 
times he  succeeded,  and  often  he  failed,  until  he  dis- 
covered the  bacillus  that  turned  the  trick,  which  de- 
veloped in  the  sour  milk,  corn-meal,  and  salt.  Where 
did  it  come  from?  Out  of  the  air!  Doctor  Kohman 

300 


SUGARS    AND    GUMS 

selected  just  the  right  bacillus,  made  cultures  from  it, 
and  to-day  any  good  baker  can  make  salt-risin'  bread 
by  using  a  culture  of  this  bacillus  instead  of  yeast. 
The  products  of  fermentation  are  hydrogen  and  CO2 
instead  of  alcohol  and  C02,  and  some  persons  find 
that  they  can  digest  this  bread  while  they  cannot 
digest  the  ordinary  product. 

Although  other  improvements  in  baking  have  ema- 
nated from  the  Mellon  Institute,  I  shall  mention  only 
one  more.  This  is  the  discovery  of  how  to  make  yeast 
do  double  work,  saving  some  flour,  one-half  the  sugar 
needed,  and  producing  a  better  bread.  The  problem 
that  Doctor  Kohman  put  to  himself  was  whether  the 
yeast,  after  it  had  finished  its  work,  had  done  the  best 
it  could.  It  feeds  on  the  very  things  contained  in  the 
flour,  so  that  it  would  seem  to  have  all  the  advantages 
that  growing  yeast  should  have.  Right  here,  I  think, 
we  can  note  the  way  scientific  training  causes  a  man's 
mind  to  work.  Here  was  yeast  growing  in  its  '  'natural 
surroundings,"  growing  just  the  way  it  has  always 
grown.  The  unscientific  mind  would  hardly  have  gone 
much  further  than  to  look  for  the  best  cultures  of 
yeast  and  the  best  flour.  Now  let  us  follow  the 
chemical  twist.  Doctor  Kohman  noted  that  the 
ashes  of  yeast  contain  a  considerable  amount  of 
calcium  and  other  metals,  and  careful  determina- 
tions confirmed  quantitatively  what  he  already  knew 
qualitatively — that  the  nitrogen  content  of  yeast  is 
high.  There  is  some  lime  and  some  nitrogenous 
protein  in  flour,  but  the  question  followed  naturally 
whether  the  yeast,  that  needs  considerable  lime  and 
fixed  nitrogen,  can  get  all  it  needs  from  the  flour  and 
milk.  So  he  tried  the  simple  experiment  of  feeding  the 
yeast  in  the  dough  batch  just  enough  of  what  it  needs 
in  the  form  of  sal  ammoniac  or  ammonium  chloride 

301 


EVERYMAN'S    CHEMISTRY 

(NH4C1)  and  calcium  chloride  (CaCl2)  mixed  with 
enough  flour  to  keep  them  dry  in  the  packages  in 
which  they  are  sold.  The  process  is  patented  in  ac- 
cordance with  the  stipulations  of  the  Mellon  Institute 
fellowships,  which  give  control  of  the  rights  to  the 
donors,  but  the  public  comes  into  the  advantages  with 
better  bread  all  around. 

Just  to  show  what  the  potential  value  is  of  a  simple 
invention  of  this  sort,  I  did  a  little  guessing  with  Doc- 
tor Kohman.  First  we  imagined  all  the  bread  in  the 
country  to  be  baked  with  the  yeast  properly  fed  as  I 
have  described.  Then  we  guessed  80,000,000  barrels 
of  flour  to  be  baked  into  bread  annually,  and  we 
proceeded  to  figure  on  the  savings.  That  would  be 
about  160,000,000  pounds  of  sugar,  at,  say,  six  cents 
a  pound,  and  80,000,000  pounds  of  yeast,  worth,  say, 
$16,000,500.  This  is  a  little  matter  of  over  $25,000,000 
a  year.  But  if  we  leave  this  item  out  of  consideration 
or  give  the  inventor  a  slice  of  it  and  the  owners  of  the 
patents  a  hunk  of  it,  we  shall  still  have  better,  more 
wholesome,  and  more  nutritious  bread. 


XXIV 

CELLULOSE   AND   NITROGEN    COMPOUNDS 

The  Universal  Need  of  Starch — Baking  Bread — What  Really  Hap- 
pens— Improvements  in  Baking — Cellulose — The  Chemistry  of 
It — Nitrocellulose — Artificial  Silk — Permanent  Paper — Fermen- 
tation Again— Paper— What  It  Is— Pulp— Sulphite  Pulp— The 
Waste  Liquor  Nuisance — The  Manufacture  of  Paper — The  Future 
in  Regard  to  Paper — A  Note  on  Nitrogen  Compounds,  including 
Proteins 

/CELLULOSE. — Here  we  have  another  polyose, 
*<-^  same  formula  as  starch  (C6H10O5)x,  but  just  as 
different  from  starch  as  can  be.  Whether  the  multiple 
of  C6HioO5  is  greater  or  less  for  cellulose  than  for  starch 
does  not  seem  to  be  clear.  Naegeli  claimed  that  by 
treating  starch  with  saliva,  salt  solutions,  and  dilute 
acids  (which  is  what  we  do  to  it  in  the  process  of  diges- 
tion) he  found  two  substances — granulose,  which  was 
soluble,  and  cellulose,  which  was  not.  If  Naegeli  was 
right,  then  cellulose  is  a  division  product  of  starch- 
but  it  doesn't  seem  established  yet.  In  fact,  it  looks 
as  though  Naegeli  was  wrong.  Cellulose  is  a  very 
sturdy  compound,  much  sturdier  than  starch.  You 
can  nitrify  cellulose  just  as  you  can  glycerin,  and 
make  nitrocellulose,  an  explosive  compound  known  as 
gun  cotton,  for  cotton  is  nearly  pure  cellulose.  If  you 
attempt  to  do  this  to  starch  it  is  apt  to  split  it  right 
down  to  sugars.  Mixed  nitric  and  sulphuric  acids 
dissolve  cellulose  to  nitrocellulose. 

303 


EVERYMAN'S   CHEMISTRY 

Very  strong  alkalies  will  also  dissolve  it,  and  so 
will  carbon  bisulphide.  A  solution  of  mononitro- 
cellulose  with  alcohol  and  ether  is  called  collodion. 
When  the  solvent  evaporates  it  leaves  an  elastic  skin. 
The  trinitrocellulose  looks  like  fibers  of  cotton  if 
made  from  that  material.  When  dissolved  in  acetone 
or  ethyl  acetate  and  the  solvent  is  removed,  it  is  used 
for  smokeless  powder.  Artificial  silk  is  made  by  dis- 
solving trinitrocellulose  in  alcohol  and  ether  and  pass- 
ing the  solution  through  very  fine  holes  in  glass  at 
a  pressure  of  about  600  pounds  per  square  inch. 
The  filaments  are  received  in  water  which  takes  up 
the  solvent,  leaving  a  very  fine  thread  which,  when  ten 
or  twenty  are  spun  together,  make  a  thread  capable  of 
being  woven.  This, however,  would  make  a  guncotton 
gown,  because  these  fibers  are  of  nitrocellulose,  and 
wrought  into  a  gown  they  certainly  would  not  do  for 
ladies  who  smoke  cigarettes.  So,  before  being  spun  or 
woven,  the  threads  are  treated  with  calcium  sulphide, 
which  takes  over  the  nitro  radicals  from  the  nitrocellu- 
lose, leaving  pure  cellulose,  which  is  just  what  is  wanted. 

The  use  of  cellulose  is  increasing  by  leaps  and 
bounds.  It  is  the  stuff  which  constitutes  the  walls 
of  the  minute  cells  of  all  vegetable  life.  It  may  be 
spun  into  threads  and  woven  into  cloth  or  felted  into 
paper.  It  may  be  made  soluble  and  resolved  into  the 
finest  threads,  and  these  again  rendered  insoluble  and 
woven  into  fabrics  of  any  thickness  desired.  Cellulose 
is  a  generic  name ;  there  are  many  different  kinds  of  it 
and  there  is  still  much  to  be  learned  about  the  struct- 
ure of  its  molecules.  Nitrocellulose  and  camphor  make 
celluloid,  and  if  acetic  acid,  which  is  another  solvent 
for  it,  were  only  cheaper,  acetyl-cellulose  would  take 
the  place  of  nitrocellulose,  as  we  have  noted  before, 
and  the  fire  hazard  of  moving-pictures  and  other 

304 


CELLULOSE,    ETC. 

celluloid  objects  would  be  removed.  Lately  Dr.  Wal- 
lace G.  Cohoe  has  invented  a  permanent  paper  for 
documents  consisting  of  a  finely  woven  cotton  cloth 
covered  with  a  thin  film  of  cellulose.  This  should  be 
good  for  five  hundred  years.  The  process  is  patented. 

Stable  and  firm  as  cellulose  is,  it  has  one  weakness, 
and  when  this  trouble  once  begins  its  days  are  num- 
bered. It  can,  by  oxidation,  go  over  to  oxy cellulose, 
which  is  its  oxidation  product.  This  is  an  utterly 
worthless,  amorphous  powder,  the  flour-like  stuff  that 
is  the  product  of  very  old  newspapers  that  crumble  to 
dust  in  your  hand.  It  may  be  produced  chemically 
by  overnitrifying  cellulose  until  the  whole  thing  is 
oxidized.  The  nitro  radicals  are  lost  in  the  process. 
But  nature  can  also  start  it  going,  especially  in  paper 
but  also  in  cloth,  and  once  cellulose  begins  to  turn  to 
oxy  cellulose  it  goes  right  on.  We  shall  come  to  this 
again  in  the  discussion  of  paper. 

Now  let  us  return  to  alcohols  once  more,  and  espe- 
cially to  ethyl  or  grain  alcohol,  which  seems  to  be 
nature's  favorite.  We  have  a  close  relation  here  be- 
tween the  alcohols,  sugars,  gums,  starch,  and  cellulose. 
While  we  cannot  polymerize  or  bunch  together  the 
sugar  molecules  until  we  have  starch,  you  may  recall 
that  by  heat  and  pressure  and  chemical  assiduity 
certain  artificial  gums  have  been  prepared.  But  we 
can  split  down  the  starches  and  cellulose  so  that  we 
get  simple  sugars  by  means  of  a  mild  acid.  Then,  in- 
stead of  doing  the  rest  ourselves,  we  call  in  the  yeast 
plant,  of  which  there  are  many  varieties,  and,  as  we 
mentioned  under  the  head  of  bread,  the  yeast  cell 
contains  two  specific  bodies,  one  of  which  oozes  out 
of  the  cell  and  converts  certain  unfermentable  sugars 
into  those  that  will  ferment.  The  difference  between 
unfermentable  and  fermentable  sugar  is  that  the  latter 

305 


EVERYMAN'S   CHEMISTRY 

will  ooze  into  the  yeast  cell,  where  it  meets  another 
enzyme,  as  these  catalytic  bodies  are  called  in  organic 
chemistry,  and  this  second  enzyme  splits  the  sugar 
into  alcohol  and  carbon  dioxide.  The  sugars  that  lack 
this  osmotic  power  to  penetrate  the  yeast  cells  are  the 
unfermentable  sugars.  Now  why  will  some  sugars  in 
solution  penetrate  that  membrane  while  others  will 
not  ?  An  easy  guess  would  be  that  monoses,  or  sugars 
of  which  the  molecules  are  composed  of  a  single  carbon 
chain,  would  slip  through  more  easily  than  those  of 
two  or  more  carbon  chains.  The  only  trouble  is, 
it  isn't  so.  Some  monoses  are  fermentable,  while 
others  are  not,  and  some  of  more  than  one  carbon  chain 
are  found  to  be  fermentable.  We  shall  have  to  let 
the  question  go  unanswered ;  but  I  should  like  to  call 
your  attention  right  here  to  a  great  field  of  chemistry 
that  we  can  only  note  in  passing,  and  that  is  biological 
chemistry.  Questions  of  fermentation  are  questions  of 
but  one  branch  of  biological  chemistry.  There  are 
innumerable  bacilli  that  turn  the  most  unexpected 
tricks  for  us,  such,  for  instance,  as  those  found  in  the 
nodules  of  leguminous  plants  that  combine  nitrogen 
of  the  air  with  some  sap  within  the  plant.  There  are 
thousands  of  different  varieties  of  bacilli,  each  of  which 
produces  a  certain  chemical  effect  under  given  condi- 
tions, and  here  is  where  the  biological  chemist,  usually 
supposed  to  be  working  on  problems  of  physiology,  is 
beginning  to  be  called  for  in  the  industrial  research 
laboratory.  Many  a  difficult  reaction  is  accomplished 
by  letting  just  the  right  bacillus  do  your  work  for  you. 
This  is  likely  to  be  one  of  the  next  great  fields  to  de- 
velop— the  biological  chemist  in  industry. 

PAPER. — Although  the  chief  ingredient  of  clothing 
is  cellulose — that  being  the  minute  framework  which 

306 


CELLULOSE,    ETC. 

makes  up  the  fibers  whether  the  stuff  be  wool,  cotton, 
linen  or  silk,  we  shall  restrain  ourselves  from  a  dis- 
cussion of  the  chemical  aspect  of  the  clothing  business 
and  consider  the  greatest  industry  dealing  chemically 
with  cellulose,  which  is  that  of  paper.  Paper  is  com- 
posed of  little  filaments  of  cellulose,  matted  or  felted 
together.  Since  cellulose  is  the  framework  of  cells, 
and  everything  that  has  life  is  made  up  of  them,  we 
should  be  able  to  make  paper  out  of  a  great  many 
different  raw  materials.  But  while  the  industry  is  a 
chemical  one,  the  knowledge  of  cellulose  and  of  its 
many  varieties  is  still  very  limited. 

For  centuries  paper  consisted  of  the  fibers  obtained 
by  the  disintegration  of  linen  and  cotton  rags,  held 
together  and  given  a  smooth  surface  by  admixtures  of 
starch,  glue,  clay,  and  similar  loading  and  surfacing 
materials.  With  increased  demand  for  paper  other 
vegetable  fibers  came  into  use.  In  this  way  wood 
pulp  was  introduced.  For  a  long  time  only  mechanical 
pulp  was  known,  and  this  is  produced  by  tearing  the 
fibers  of  soft  wood  asunder,  grinding  diagonally  the 
edges  of  the  natural  logs  with  a  stone  in  the  presence 
of  water.  These  particles  contain  a  large  part  of  the 
gums  and  other  substances  of  the  tree  which  are  less 
stable  than  cellulose.  They  oxidize  on  long  exposure, 
and  oxidation,  whether  slow  as  in  this  instance,  or 
rapid  as  with  fire,  is  likely  to  be  contagious ;  and  when 
the  whole  paper  is  transformed  to  oxycellulose  it  be- 
comes worthless.  As  we  noted  a  few  pages  back, 
oxycellulose  is  an  amorphous  powder  with  no  mechan- 
ical qualities  whatever. 

Mechanical  wood  pulp  was  formerly  mixed  with 
that  made  of  rags,  to  its  cheapening  and  detriment; 
and  the  rule  holds  good  to  this  day  that  the  more  of 
this  mechanical  pulp  a  paper  contains  the  poorer 

307 


EVERYMAN'S    CHEMISTRY 

is  its  quality.  Later  a  Philadelphia  chemist  named 
Tilghman  made  an  important  discovery.  He  observed 
that  sulphurous  acid  has  a  disintegrating  action  upon 
wood,  setting  the  cellulose  fibers  free  from  incrusting 
substances,  and  this  gave  a  great  impetus  to  the  paper 
industry.  The  usual  method  is  to  treat  chips  of  wood, 
hacked  out  so  as  to  give  a  good  length  of  fiber,  with 
bisulphite  of  soda,  and  the  sulphurous  acid  which  is 
set  free  dissolves  all  the  organic  substances  except  the 
cellulose.  It  takes  place  under  heat  and  pressure. 
This  is  sulphite  pulp,  after  it  has  been  treated  with 
water  to  separate  the  fibers  and  bleached.  To  make  a 
good  newspaper  requires  about  20  per  cent,  of  this 
product,  along  with  the  mechanical  pulp. 

A  stronger  quality  of  sulphite  pulp  is  made  by  the 
Mitscherlich  process,  in  which  a  weaker  acid  is  used. 
This  points  the  way  to  improvements  in  the  art,  such 
as  the  lately  developed  kraft  paper — a  very  strong 
wrapping-paper  made  originally  of  undercooked  pulp. 
It  has  also  developed  what  is  known  as  the  sulphate 
process,  which,  owing  to  its  milder  treatment  of  the 
wood,  is  finding  increased  application. 

We  should  note  right  here  that  sulphite-pulp  mills 
have  been  a  great  nuisance,  because  of  their  waste 
liquors.  That  sulphurous-acid  solution  contains  every- 
thing in  the  tree  except  the  cellulose,  and  it  pollutes 
streams,  kills  fish,  and  it  takes  a  long-suffering  public 
and  easy-going  lawmakers  to  stand  that  sort  of  thing. 
Modern  methods  of  dehydration  bring  the  solute  down 
to  a  powder  which  bids  fair  to  have  many  uses.  There 
has  also  been  discovered  a  curious  yeast  plant  that 
thrives  in  a  sulphurous-acid  solution.  By  means  of 
this  the  waste  liquors  are  treated  so  as  to  produce 
about  i  per  cent,  of  alcohol,  and  the  production  of 
ethyl  (or  grain)  alcohol  from  this  source  is  increasing 

308 


CELLULOSE,    ETC. 

rapidly.  So  is  the  impatience  of  the  public  with  the 
waste-liquor  nuisance  of  those  sulphite-mills  which  do 
not  treat  their  liquors. 

The  first  process  in  paper-making  is  to  put  the 
pulp  into  a  tub  called  a  beater,  in  which,  with  a  great 
deal  of  water,  the  pulp  is  made  to  revolve  around  a 
center,  or  " teased,"  as  the  expression  is,  to  get  the 
fibers  softened.  The  quality  of  paper  to  be  made  is 
determined  in  the  beater.  Then  clay  is  added  to 
about  15  per  cent,  of  the  weight  of  the  pulp,  of  which 
about  5  per  cent,  is  retained  in  the  final  product,  and 
then  red  coloring-matter  is  put  in  to  overcome  the 
yellow  tinge  of  the  wood,  after  which  blue  is  added  to 
make  it  nearer  white. 

After  coloring,  some  milk  of  rosin  is  thrown  in. 
This  is  ordinary  rosin  emulsified  with  soda  ash,  and 
is  called  engine  sizing.  In  the  cheaper  grades  very 
little  rosin  is  used.  This  is  followed  by  alum,  which 
distributes  the  rosin,  but  why  it  does  so  is  more  than 
I  can  answer.  Let  us  say  that  it  is  for  some  colloidal 
reason  and  hurry  along  to  the  next  subject.  All  the 
time  the  fibers  have  been  in  constant  motion,  and  when 
a  thorough  mixing  has  been  reached  the  bottom  of  the 
tub  is  opened  and  the  mass  drops  down  into  what  is 
called  a  staff  chest.  This  is  a  large  box  agitated  with 
a  paddle  into  which  water  constantly  pours.  From 
here  it  is  pumped  up  to  the  paper-machine  floor,  where 
it  is  first  refined  in  what  is  called  a  Jordan,  which  is 
constructed  like  a  meat-chopper,  and  again  it  is 
screened,  with  water  pouring  over  it  all  the  time.  It 
takes  about  one  thousand  gallons  of  water  to  make 
one  pound  of  paper.  Then,  as  a  thin,  milky 
fluid,  it  is  run  into  the  flow-box  of  the  machine. 
This  is  a  long  table  of  wire  screen,  through  which  the 
water  flows  as  the  fibers  are  distributed  upon  it.  The 

309 


EVERYMAN'S   CHEMISTRY 

screens  are  about  sixty  feet  long  and  from  sixty  to 
two  hundred  inches  wide.  By  very  cleverly  devised 
joggling  motions  of  the  screens,  which  move  very 
rapidly,  the  fibers  are  so  laid  that  the  paper  has,  in 
effect,  a  warp  and  a  woof.  From  the  screen  the  paper 
is  picked  up  and  passed  through  drying-rolls,  where  the 
rosin  becomes  more  evenly  distributed.  If  the  paper 
is  to  be  sized,  it  is  passed  through  a  trough  of  glue. 
It  is  then  reeled  and  cut. 

Thus  the  art  of  making  paper  is  further  advanced 
than  the  science  of  it.  To  furnish  the  United  States 
with  paper  requires  the  trees  growing  on  several  mill- 
ion acres  every  year,  and  not  only  is  there  not  enough 
spruce,  balsam,  fir,  hemlock,  chestnut,  and  poplar, 
but  it  seems  a  shame  to  use  the  forests  up  this 
way.  If  these  woods  were  cut  and  the  wood  planta- 
tions maintained  according  to  enlightened  forestry,  no 
harm  would  be  done,  although  less  paper  would  be 
made.  But  we  do  not  do  things  that  way  on  a  large 
scale  in  this  country  as  yet.  We  cut  and  slash  through 
any  old  way  that  will  pay  best,  and  that  is  sometimes 
very  bad  for  the  land  and  the  people.  I  do  not  know 
how  to  keep  up  our  paper  supply  and  conserve  our 
forests  at  the  same  time,  so  that  my  complaint  is  not 
much  more  than  a  whine,  at  the  best.  What  is  needed 
is  something  to  take  the  place  of  these  woods,  and 
not  only  United  States  Government  chemists,  but 
other  men  of  research,  are  diligently  engaged  on  the 
problem. 

The  first  thing  to  utilize  will  probably  be  wood 
waste.  Sawdust  has  not  long  enough  fiber,  but  slabs 
and  stumps,  branches,  and  roots  will  probably  be 
availed  of  as  soon  as  economical  methods  are  devised. 
Dr.  Arthur  D.  Little,  of  Boston,  a  well-known  author- 
ity, estimated  the  daily  waste  of  possible  paper  in  the 

310 


CELLULOSE,    ETC. 

yellow-pine  industry  alone  to  be  40,000  tons!  The 
making  of  kraft  paper  from  slabs  and  other  waste 
is  now  rather  a  matter  of  engineering  and  transporta- 
tion than  of  research.  Some  work  is  in  process  already. 
Corn-stalks,  rice  and  flax  straw,  cotton-stalks,  and 
the  wild  banana  are  far  from  a  complete  list  of  other 
possible  sources  of  pulp  supply.  A  very  interesting 
process  well  past  the  theoretical  stage  is  the  dehydra- 
tion of  sugar-cane  on  the  plantation  and  the  shipment 
of  dried  and  baled  cane  for  the  sugar  to  be  extracted 
in  temperate  climates.  We  referred  to  this  in  dis- 
cussing the  manufacture  of  sugar.  It  would  not  only 
enable  the  sugar-works  to  operate  all  the  year  round 
in  temperate  climates  instead  of  for  a  short  season 
when  the  cane  is  ripe  in  the  tropics,  but  it  would 
also  make  the  planters  independent  of  the  tropical 
sugar  centrals.  The  resultant  paper  is  of  very  fine 
quality. 

In  Europe  a  grass  grown  in  the  southern  part  of 
the  continent  and  in  northern  Africa  called  esparto 
is  very  widely  used,  and  the  wild  banana  of  tropical 
and  subtropical  America  is  full  of  promise.  But  we 
haven't  got  around  to  it  yet,  and  so  far,  'so  long 
as  spruce  and  other  soft  woods  hold  out,  they  are 
cheaper. 

Aside  from  the  need  of  new  sources  of  pulp  supply, 
paper-makers  would  like  somebody  to  invent  an  im- 
proved screen  for  their  Fourdrinier  machines.  These, 
upon  which  the  paper  is  finally  made,  consist  of  cop- 
per, and  copper  breaks — the  screens  are  not  strong 
enough.  If  somebody  will  be  good  enough  to  invent  a 
non-corrosive  alloy  with  great  tensile  strength  that 
costs  no  more  than  copper,  the  paper-making-machin- 
ery people  will  have  something  to  say  to  him  for  his 
own  good. 

21 


EVERYMAN'S    CHEMISTRY 


NITROGEN    COMPOUNDS 

Amines.  —  Ammonia,  NH3,  has  a  way  of  exchanging 
hydrogen  atoms  for  paraffin  radicals,  and  these  are 
called  amines.  Without  going  into  details  there  are 
combinations  of  methane,  CH4,  and  ethane,  C2H6,  with 
ammonia  as  follows  : 


r//    Primary  Mefhy  famine 
H 

/CH? 

\Crfj   Dimethylamme 

H 
/*  i 

Tnmefhytamine 
Methy/ethy/amme 

In  other  words,  they  may  be  regarded  as  derivatives 
of  ammonia.  The  lower  members  are  gases,  inflam- 
mable, and  are  very  soluble  in  water.  The  succeeding 
members  have  low  boiling-points  and  are  miscible 
with  water.  Both  they  and  the  lower  orders  have  a 
characteristic  smell,  something  like  boiled  lobsters. 
The  higher  members  are  odorless  and  insoluble  in 
water. 

NITRO  COMPOUNDS.  —  These  contain  a  N02  group, 
the  nitrogen  atom  being  directly  linked  to  carbon. 
CH3NO2  is  nitromethane,  C2H5NO2  is  nitroethane, 
etc.  They  have  the  peculiarity  of  exchanging  one 
hydrogen  atom  for  an  alkali  metal,  especially  sodium. 
Thus 

C2H6N02     -f    Na     =     CANaNOa     +    H 
nitroethane      sodium 

312 


CELLULOSE,    ETC. 

and  these  sodium  compounds  are  insoluble  in  absolute 
alcohol,  which  gives  the  chemist  the  key  to  their 
separation. 

Carbylamines. — Of  course  the  cyanogen,  C2N2,  radi- 
cal will  turn  up,  and  this  it  does  in  two  different  ways : 
with  the  nitrogen  atom  linked  to  the  alkyl  group,  as, 
for  instance,  C2H6.NC,  which  is  carbylamine  or  ethyl 
isocy amide.  Another  name  for  the  group  is  isonitriles. 
They  smell  to  high  heaven.  The  general  character- 
istic is  a  rank,  pungent  odor  of  Simon-pure  filth. 

Proteins. — A  possibility,  but  still  an  unsolved  riddle, 
is  the  synthetic  production  of  protein.  Protein  is 
a  generic  name  given  to  those  complex  bodies  con- 
sisting of  carbon,  hydrogen,  oxygen,  and  nitrogen 
found  in  both  animal  and  vegetable  products  which, 
by  the  metabolism  of  the  body,  are  changed  into  tissue. 
It  is  the  stuff  that  makes  muscle,  and  without  protein 
we  cannot  live.  They  have  molecules  of  great  com- 
plexity, and  in  addition  to  the  elements  named  they 
carry  sulphur,  phosphorus,  and  other  elements.  The 
great  Emil  Fischer,  after  clearing  up  the  sugar  mys- 
teries and  blazing  the  trail  so  that  nearly  every  pos- 
sible sugar  is  now  known,  set  himself  to  the  task  of 
untangling  the  protein  riddle,  and  he  succeeded  in 
producing,  synthetically,  certain  polypeptides  which, 
had  they  first  been  discovered  in  nature,  would  surely 
have  been  classed  as  proteins.  This  is  just  getting 
under  the  edge  of  the  subject,  and  I  think  it  doubtful  if 
this  generation  will  see  the  synthetic  production  of 
the  stuff  that  meat  is  made  of  brought  into  general 
practice.  On  the  other  hand,  it  will  be  interesting  to 
learn,  when  the  European  war  is  over,  how  much  has 
been  accomplished  in  the  way  of  research  to  provide 
synthetic  foods  in  Germany  during  the  blockade.  It 
is  possible  that  necessity  may  have  incited  some  very 

313 


EVERYMAN'S    CHEMISTRY 

considerable  advances  where  chemical  research  has 
reached  so  high  a  stage  as  it  has  in  that  country. 
They  have  not,  apparently,  been  able  to  raise  enough 
vegetable  oils  to  be  hardened  into  the  much-needed 
fats. 


XXV 

AROMATIC   COMPOUNDS 

The  Benzol  Ring— Why  These  Compounds  Are  Called  Aromatic — 
The  Ways  of  the  Benzol  Ring — How  the  Aromatics  Are  Formed — 
Tar — The  Series — Nitrification — Picric  Acid — Other  Aromatic 
Acids — Positions  on  the  Ring — Higher  Aromatic  Hydrocarbons 

WE  must  treat  in  a  still  slighter  manner  the  other 
half  of  organic  chemistry,  with  a  view  to  giving 
an  intimation  of  the  great  industries  built  upon  the 
so-called  derivatives  of  coal-tar. 

Substantially  all  of  the  products  heretofore  consid- 
ered in  organic  chemistry  have  consisted  of  open 
chains  of  carbon  atoms  linked  to  one  another  by  one 
and  occasionally  two  and  three  bonds.  Now  we  come 
to  compounds  in  which  six  carbon  atoms  form  the 
nucleus  of  the  molecule  or  group  of  atoms,  attached  to 
one  another  in  the  form  of  a  hexagon  or  ring.  This 
is  the  famous  benzol  ring  which  is  so  often  spoken  of 
in  chemistry.  The  formula  is  C6H6,  and  it  is  graph- 
ically presented  as  follows : 

Ji 


c 
H 


EVERYMAN'S    CHEMISTRY 
It  is  often  represented  as  a  simple  hexagon, 


or 


,    with    all    the    carbon    and 


hydrogen  atoms  supposed  to  be  present  except  where 
a  substitution  is  made,  as,  for  instance,  in  chlorben- 
zol,  C6H6C1, 


It  acts  somewhat  like  an  atom  with  six  bonds  at- 
tached to  hydrogen,  except  for  the  fact  that  a  few 
compounds  are  known  in  which  a  carbon  atom  is 
replaced  by  that  of  another  element,  but,  generally 
speaking,  that  ring  of  six  carbons  holds  tight  together. 
The  substitutions  take  the  places  of  the  hydrogen 
atoms.  Benzol,  C6H6,  is  also  spelled  benzene,  and  is 
not  to  be  confounded  with  petroleum  benzine,  which 
is  a  solvent  composed  of  aliphatic  hydrocarbons  and 
is  generally  lighter  than  gasolene. 

There  are  fashions  and  styles  in  all  things  from 
bonnets  to  coffins,  and  there  are  fashions  and  styles  in 
chemistry,  even  in  chemical  names.  The  termination 
"ene"  for  the  primary  bodies  of  the  aromatic  group, 
such  as  benzene,  toluene,  xylene,  etc.,  seems  to  be  in 
greater  favor  now  than  "ol."  Being  somewhat  of  an 
old  fogy  myself,  my  pen  is  likely  to  slip  into  habits 

316 


AROMATIC   COMPOUNDS 

of  expression  familiar  to  my  youth  and  to   write 
frequently  of  benzol,  etc. 

These  benzol  rings  are  also  known  in  double  com- 
pounds, in  naphthalene,,  Ci0H8,  or 


H 
i 

,C 


//— c 


C~H 


H         H 
and  triplet,  as  in  anthracene, 


or 


H 

I 


H 
\ 


"-VVV-" 

I  I  I 

H        H         H 


Now  if  these  carbon  atoms  are  in  groups  of  six,  they 
must  have  a  certain  form,  the  molecules  must  have 
length,  breadth,  and  thickness  instead  of  being  geo- 
metric planes.  But  we  shall  not  enter  into  that  prob- 
lem ;  the  ring  is  easily  imagined  and  it  serves  its  pur- 
pose. 

The  name  aromatic  came  about  through  the  dis- 
covery that  certain  vegetable  substances  such  as  oil 


EVERYMAN'S   CHEMISTRY 

of  bitter  almonds,  cumin,  vanilla,  etc.,  contained  much 
less  hydrogen  in  proportion  to  the  carbon  than  fatty 
bodies  with  the  same  number  of  carbon  atoms  in  the 
molecule.  It  was  also  discovered  that  these  com- 
pounds built  themselves  up  about  the  benzol  ring. 
So  the  name  held,  although  all  benzol  derivatives  are 
no  more  odorous  than  is  so-called  "butter  of  anti- 
mony," SbCl3,  a  butter,  or  the  "sugar  of  lead"  (ace- 
tate of  lead),  a  sugar.  It  is  just  a  name,  and  the 
aromatic  compounds  are  those  that  contain  benzol  as 
the  nucleus,  while  the  paraffins  or  aliphatic  bodies 
might  be  said  to  be  derivatives  of  methane,  CH4. 

We  shall  have  to  skip  so  much  in  order  to  get  at  a 
hasty  consideration  of  dyestuffs  and  the  like  that  you 
must  take  all  sorts  of  things  for  granted.  Please  ac- 
cept the  statement,  for  instance,  that  there  are  aro- 
matic acids  and  ethers  and  esters  and  aldehydes  and 
ketones,  just  as  there  are  aliphatic  bodies  of  this  type. 

We  may,  however,  consider  a  few  tricks  of  this  ben- 
zene ring  just  as  a  reminder  that  we  are  in  a  different 
field  from  that  of  the  carbon  chains.  The  saturated 
hydrocarbons  of  the  paraffins  are  not  attacked  by 
concentrated  acids,  and  oxidizing  agents  affect  them 
only  slightly.  The  benzol  ring,  on  the  other  hand,  is 
not  so  robust  in  this  respect.  It  is  neither  an  acid 
nor  a  base,  but  when  attacked  by  sulphuric  acid,  for 
instance,  the  resultant  bodies  are  another  acid  and 
water.  The  acid  is  called  benzolsulphonic  acid,  and 
in  the  making  of  this  one  oxygen  atom  of  the  sulphuric 
acid  goes  with  one  of  its  own  hydrogen  atoms  and  one 
from  the  benzene  ring  to  produce  H^O.  Here  is  the 
reaction  : 


CeH6     +     H2SO4     =     CeHsHSOs     +     H2O 
benzol         sulphuric          benzolsul-  water 

acid  phonic  acid 

318 


AROMATIC    COMPOUNDS 

Nitric  acid,  HNO3,  will  do  the  same  thing,  leaving  a 
NO2  group  attached  to  the  molecule. 

When  vapors  of  the  aliphatic  compounds  or  carbon 
chains  are  passed  through  a  red-hot  tube,  aromatic 
substances  are  among  the  products.  Heat  and  press- 
ure, in  the  absence  of  air,  induce  the  production  of 
aromatic  compounds.  And  Nature  produces  them  in 
her  own  quiet  way,  as  she  pleases. 

When  coal  is  heated  in  iron  retorts,  raised  to  red 
heat,  the  gas  goes  out  with  other  vapors  while  coke 
remains  behind  in  the  retorts.  Just  what  all  the  bodies 
were  that  were  in  the  coal  before  it  was  destroyed  by 
distillation  nobody  knows;  it  is  one  of  the  chemical 
nuts  not  yet  cracked.  The  reason  is  that  as  soon  as 
you  begin  to  heat  it  the  bodies  change,  and  so  we  know 
what  is  produced  by  the  distillation,  but  we  do  not 
know  how  these  atoms  were  matched  up  in  molecules 
before.  We  know  it  was  not  pure  coal,  because  we 
get  so  many  hydrocarbons  and  so  much  ammonia 
from  it. 

The  first  product  is  a  gas,  mainly  carbon  monoxide, 
CO,  and  with  it  goes  some  unsaturated  hydrocarbons, 
some  cyanogen,  C2N2,  some  sulphur  dioxide,  and  also 
some  of  the  lighter  aromatic  bodies  such  as  benzol, 
toluol,  and  xylol. 

The  gas  liquor  which  comes  from  washing  the  gas 
with  water  contains  chiefly  ammonia.  The  next  goes 
by  the  generic  name  of  tar,  and  this  is  what  we  have 
to  do  with  now,  while 

Coke  remains  behind,  which  is  approximately,  but 
by  no  means  wholly,  pure  carbon. 

The  tar  is  distilled  again  and  we  have  as  products: 

1.  Light  oil.  3.  Heavy  oil. 

2.  Middle  oil.  4.  Refined  tar, 

5.  Pitch. 
3T9 


EVERYMAN'S    CHEMISTRY 

The  light  oil  contains  benzol,  toluol,  the  second  of 
the  group,  and  xylol,  the  third  member,  and  some  of 
the  heavier  bodies. 

The  middle  and  heavy  oils  contain  the  heavier 
members  of  the  aromatic  group. 

Refined  tar  contains  pitch  with  the  heaviest  bodies, 
and  pitch  is  pitch.  It  is  used  for  roofing,  and  lately 
a  method  has  been  discovered  and  patented  for  con- 
verting it  into  coke.  This  was  no  little  triumph,  for 
European  chemists  have  been  trying  to  do  this  for 
many  years. 

Pitch  is  one  of  those  by-products  for  which  the  tar- 
distillers  have  long  sought  in  vain  a  good  use.  Roofing, 
etc.,  takes  up  only  a  very  small  fraction  of  that 
which  is  produced.  So  to  turn  it  into  coke  is  a  great 
achievement,  provided  always  the  discovery  pans  out 
well.  So  far  as  I  know  it  is  not  yet  in  operation  on  a 
large  scale,  therefore  the  pitch  problem  is  still  a  prob- 
lem— at  least  with  most  coal-tar  distillers. 

Now  just  as  methane  is  the  starting-point  for  the 
aliphatic  compounds,  so  benzol  is  the  starting-point  in 
this  series.  From  ^  to  i  per  cent,  of  coal-tar  is  benzol 
and  toluol,  and  there  is  more  benzol  than  toluol  found. 
Toluol  is  benzol  with  one  hydrogen  atom  replaced  by 
a  methyl  group : 

' 


H 

benzol  toluol 

320 


AROMATIC   COMPOUNDS 

The  third  is  xylol,  C6H4(CH3)2,  and  so  the  substitu- 
tions of  H  atoms  in  the  benzol  molecule  continue. 
Here  are  a  few  of  them  : 

Benzol  or  benzene,  CeHe  Boils  at    80  .  4° 

Toluol  or  toluene,  CeHsCHa  "      "    110° 

Xylene,  C6H5(CH3)2  "      "   139° 

Mesitylene,  CBH8(CHs)s  '    164° 

Then  we  have  ethylbenzene,  C6H5C2H5,  and  innumer- 
able others. 

Just  as  we  can  nitrify  benzol  and  make  nitro- 
benzol,  so  we  can  add  nitro  radicals  not  only  to 
benzol,  but  to  toluol  and  the  other  members  of  the 
series.  They  are  heavy,  oily,  and  some  of  them  are 
solid.  It  makes  a  difference  just  where  the  substitute 
bodies  go  upon  the  ring.  In  making  nitrotoluol,  e.g., 
let  us  say  the  methyl  or  CH3 
group  is  at  point  No.  i.  Then  ./ 

if  the  NO2  attaches  itself  at  point  2    orfhod         zOrtho 
or  upon   the  shoulder  it  is  ortho- 
nitrotoluol.     If  at  point  4  or  at  the 
foot  it  is  paranitrotoluol,  and  if  at     Mefas 
point  3  or  at  the  knee  it  is  meta- 
nitrotoluol.     If  a  nitro  body  or  NO2 
is  attached  to  all  these  places  it  is 
trinitrotoluol    or    trinitrotoluene,    CH3.C6H2.(NO2)3, 
and  this  is  the  famous  T.N.T.  used  by  the  armies 
in  siege-guns. 

If  nitrobenzol  is  reduced  by  means  of  iron  filings 
and  muriatic  acid,  we  have  the  reaction 


3Fe  +  6HC1   =  C6H5NH2  +  2H20  +  FeCl2 

nitro-          iron       hydro-  •  aniline          water       ferrous 

benzol                       chloric  chloride 
acid 

Aniline  is  the  starting-point  for  many  dyestuffs,  but 
let  us  put  off  consideration  of  these  for  the  present. 

321 


EVERYMAN'S    CHEMISTRY 

Starting  with  phenol  or  carbolic  acid,  C6H5OH,  let 
us  proceed  to  nitrify  it  with  mixed  nitric  and  sulphuric 
acids.  Then  we  shall  finally  have  trinitrophenol, 
or  picric  acid,  which  is  at  once  a  yellow  dyestuff  and 
an  explosive.  Left  by  itself,  however  it  will  not  ex- 
plode, and  if  it  is  dissolved  in  a  test-tube  in  hot  water 
and  allowed  to  cool,  the  long,  spear-like,  yellow 
crystals  form  in  a  beautiful  manner.  It  is  a  very 
pretty  chemical  show. 

If  we  start  with  benzol  again,  and  add  COOH  to 
make  benzoic  acid,  and  then  substitute  OH  for  three 
more  hydrogens,  we  have  gallic  acid, 
C^OOrt        which   is    found    in    gall-nuts,   tea, 
H—C        C—H     "divi  -  divi,"     and     many     plants. 
Closely  allied  to  this  are  the  tan- 
nins, or  tannic  acids,  which  are  very 
Ort—C.       C—OH  widely  distributed  in  the  vegetable 
C  kingdom.   Tannin  is  a  bitter  astrin- 

0L  gent  used  in  tanning  leather  and  in 

Goll/c  Acid         medicine.     In  making   leather  the 
hide  is  saturated  with  tannin  be- 
cause without  it  it  soon  dries  to  a  hard,  horn  -like  sub- 
stance which,  when  moist,  becomes  rotten.    Tannin 
renders  it  pliant  and  permanent. 

The  benzol  ring  is  as  whimsical  as  an  Irish  lass. 
Note  again,  please,  the  three  positions,  ortho,  meta, 
and  para. 

/  \  Now  whether  a  body  attaches  it- 

zOrtho  positions 


may  be  partially   but  not  wholly 
controlled    by    temperature     and 
Meta     pressure,  while  the  meta  position 
is  likely  to  be  taken  up  after  the 
other  two  are  occupied,  but  not  al- 
ways, by  any  means.    Positions  4  and  5,  which  are  also 

322 


AROMATIC   COMPOUNDS 


respectively  meta  and  ortho  positions,  may,  and  again 
may  not,  let  some  radical  attach  itself  in  the  place  of 
the  hydrogen.  It  requires  all  the  trickiness  of  an  am- 
bulance-chasing lawyer  to  negotiate  some  of  the  aro- 
matic combinations.  You  can  make  mononitrotoluol, 
binitrotoluol,  and  trinitrotoluol  if  you  please,  but  as 
soon  as  you  have  three  NO2  groups  attached  if  you 
attempt  to  nitrify  it  any  more  you  oxidize  the  whole 
thing.  This  trickiness  of  the  benzol  ring  is  why  it 
takes  so  many  chemical  specialists,  for  instance,  in 
the  dyestuff  industry,  and  it  explains  why  the  explo- 
sives-works need  such  great  research  laboratories. 
There  are  rules,  but  they  are  so  many  and  so  con- 
flicting that  it  requires  intense  familiarity  with  the 
individual  bodies  to  be  able  to  change  them  as  desired. 
We  noted  that  there  were  higher  hydrocarbons  in 
coal-tar  that  came  over  more  especially  with  the  heavy 
oil.  These  were  coupled  and  tripled  benzol  mole- 
cules, known  as  naphthalene,  CioH8,  and  anthracene, 
d4Hio,  both  of  them  solids  at  ordinary  temperatures. 


H          H 
C        I 


H 


U 


H 


//— c 


- 


H 


H 


H 


Naphthalene  is  the  white,  crystalline  substance 
used  for  moth-balls,  while  anthracene,  of  which  coal- 
tar  contains  less  than  it  does  of  naphthalene,  crystal- 
lizes in  bluish  leaflets.  Both  are  largely  used  in 
making  dyes. 

323 


EVERYMAN'S    CHEMISTRY 

The  chemical  philosophy  of  dyestuffs  is  not  at  all 
simple.  If  they  were  a  series  of  bodies  of  one  kind 
like  the  paraffins,  the  fatty  acids,  the  alcohols,  or  even 
the  sugars,  the  problems  would  be  easier  to  explain. 
Of  course  there  is  a  reason  for  these  tinctorial  qualities, 
but  it  takes  a  keen  vision,  a  large,  catholic  sense  of  the 
reactions  of  organic  chemistry,  to  see  them,  and  even 
then  I  may  add  that  the  Great  Tinctorial  Principle  is 
not  very  clearly  defined. 

There  are  three  general  orders  of  compounds  which 
we  have  to  deal  with  in  this  industry  which  is  closely 
be-cousined  with  that  of  making  explosives,  many 
photographic  chemicals,  synthetic  perfumery,  a  large 
number  of  medicines,  and  all  sorts  of  other  things. 
These  three  orders  are,  respectively,  crudes,  which 
involve  the  products  distilled  from  tar,  such  as  benzol, 
toluol,  carbolic  acid,  naphthalene,  and  the  like  which 
come  from  the  coal-tar  distillers;  the  second  are 
known  as  intermediates,  of  which  you  shall  soon  learn; 
and  the  third  are  the  finished  products.  These  in- 
dustries overlap  more  or  less,  but  they  are  distinct, 
and  each  one  is  full  of  problems  of  its  own.  In  regard 
to  finished  products,  no  one  establishment  has  ever 
been  able  to  cover  the  entire  ground,  and  the  same 
might  be  said  of  the  intermediates  if  the  term  were 
not  so  indefinite.  The  reactions  are  very  subtle,  and 
a  great  deal  of  specializing  is  called  for.  The  industries 
are  remarkably  interdependent,  and  I  think  it  will 
soon  become  clear  to  you  why  ''we" — which  means 
the  chemical  industry  of  America — cannot  proceed  to 
put  up  a  few  shacks  and  turn  out  all  the  dyestuffs 
there  are  by  a  mere  resolution  to  do  so.  There  are 
about  two  thousand  different  synthetic  dyes  known, 
but  all  that  we  shall  do  will  be  to  indicate  a  few  of  the 
leading  intermediates  and  then  tell  something  of 

324 


AROMATIC   COMPOUNDS 

several  important  colors.  All  that  we  shall  try  to  do 
is  to  lift  the  lid,  just  a  little,  to  show  the  kind  of  pro- 
cedure involved  in  this  field  of  applied  chemistry. 

Let  us  begin  by  mentioning  a  few  intermediates 
which  are  made  from  the  crudes,  while  the  dyestuffs 
are  made  from  the  intermediates. 


XXVI 

COAL-TAR    INTERMEDIATES     AND    FINISHED    PRODUCTS 

Aniline  and  Other  Intermediates — Colors — Vat  Dyes — Position  of 
Dyestuff  Industry  in  the  United  States — Position  of  Chemical 
Industry  in  the  United  States — Good-by 

ANILINE,  as  we  have  noted  before,  is  benzol  with 
**  one  NH2  group  in  the  place  of  one  of  its  hydrogen 


atoms. 


Paranitraniline  is  aniline  with  an  NO2  group  in  the 


para  position 


Paranrfranilme 
326 


COAL-TAR  AND   FINISHED   PRODUCTS 

Toluidine  is  toluol.  C6H5CH3,  with  the  NH2  group 

CH5 

i 

attached. 


Phenol  is  carbolic  acid  or  benzol  with  an  OH  group, 
OH 


C6HBOH. 


This  is  found  in  tar  and  is  also 


made  synthetically,  starting  with  benzol. 


Naphthalene,  Ci0H8, 


is  rather 


a  crude,  such  as  benzol,  and  naphthol  is  like  car- 
bolic acid,  except  that  we  start  with  naphthalene 
instead  of  benzene.  The  two  bodies  with  the  OH 
radical  in  two  different  positions  are  needed  for  dif- 
22  327 


EVERYMAN'S    CHEMISTRY 

ferent  purposes.     In  alpha  naphthol  the  OH  group  is 
in  the  alpha  or  first  position, 


In  beta  naphthol  the  OH  group  is  in  the  second  or 
beta  position, 


If  you  remember  that  phenol  or  carbolic  acid  is 


OH 

x\ 


\x 


and  naphthol  is 


it  would 


appear  that  the  naphthols  should  be  good  disinfect- 
ants, and  you  would  be  right.  Here  I  throw  in  with 
the  price  of  the  book  a  recipe  for  one  of  the  best  hair 
tonics  and  dandruff  cures :  One-half  of  one  per  cent. 

328 


COAL-TAR  AND   FINISHED   PRODUCTS 

of  beta  naphthol  dissolved  in  alcohol.  If  the  scalp  is 
dry,  dissolve  a  little  castor-oil  in  it  and  make  it  as 
oily  as  you  need. 

Beta  naphthol  has  a  slight  odor,  but  is  a  remark- 
able deodorant.  The  naphtholes  are  made  by  fusing 
naphthalene  sulphonic  acids  with  caustic  soda. 

Alpha  and  beta  naphthylamine  correspond  to  alpha 
and  beta  naphtholes  with  NH2  in  the  place  of  OH, 
and  may  be  compared  chemically  with  aniline,  naph- 
thylamine being  described  as 


NHL 

/V\ 


or 


NH2 


Alpha  Ncrpfhy/amine       Be  fa  Nctpthylamine 


whereas  aniline  is 


NM2 

/\ 


I  do  not  know  whether 


naphthylamines  are  poisonous  or  not,  but  they  smell 
badly  enough  to  keep  everybody  away  from  them 
that  has  no  business  with  them. 

H  acid,  so  called,  is  i — 8 — 3 — 6,  amidonaphtholdi- 
sulphonic  acid. 

329 


EVERYMAN'S   CHEMISTRY 

OH       NH 


HAcut 

This  is  very  difficult  to  make  until  you  know  just 
how,  and  then  it  is  easy.  I  only  know  of  two  concerns 
that  are  producing  it  successfully  in  the  United  States 
at  the  time  of  this  writing.  Before  the  book  is  printed 
others  may  be  making  it. 

Aniline  was  first  obtained  by  the  dry  distillation  of 
indigo,  from  which  it  derives  its  name,  the  Spanish 
word  for  indigo  being  anil.  It  is  a  colorless  liquid, 
oily,  peculiar  smelling,  and  boils  at  183°  centigrade. 
It  has  an  odd  kind  of  poisonous  effect:  if  a  small 
quantity  of  aniline  is  spilled  upon  the  clothing  or  the 
skin,  it  is  readily  absorbed,  the  lips  turn  blue,  the  skin 
white,  and  a  general  collapse  follows.  The  dyes  made 
from  aniline  have  not  these  effects;  men  may  work 
in  them  and  be  smeared  with  them  continually  with 
no  ill  effects. 

If  we  bring  together  three  molecules  of  toluidine 
and  aniline  and  oxidize  them  with  arsenic  acid  or 
nitrobenzol,  we  get  a  combination  as  follows: 


HO~C-C6H4~NH2 
C6H4-NH2 

Co  tor  base  ofan/7/ne, 
red  or  ma  gen  fa 

which  is  the  color  base  of  aniline  red  or  magenta  or 
fuchsine  as  it  is  sometimes  called. 

330 


COAL-TAR  AND  FINISHED  PRODUCTS 

The  chloride  of  this  color  base, 


Maaenfa 

is  magenta  itself. 

As  we  substitute  a  phenyl  group,  as  benzol  less  one 
hydrogen  atom  is  called  (C6H5)  into  the  places  of 
hydrogen  atoms  in  the  red,  we  get  aniline  blue;  the 
more  phenyl  groups  the  more  greenish  the  blue. 

Azo  COLORS. — There  is  a  series  known  as  "azo" 
compounds  of  benzol  of  which  the  simplest  would  be 
CeKU.NHN.CeHs.  These  two  nitrogen  atoms  in  the 
molecule  behave  like  a  central  hinge  and  give  the 
name  diazo  to  compounds  of  which  the  C6H5N2  group 
forms  a  part.  This  diazonium  group  behaves  some- 
thing like  the  ammonium  radical  —  NH4  in  its  habits 
of  combination.  Generally  speaking,  the  azo  colors 
are  obtained  by  treating  diazonium  chlorides  with 
aromatic  amines  or  with  phenols.  The  simplest  azo 
dyes  are  yellow.  Then,  as  alkyl  or  phenyl  groups 
(paraffins  or  aromatic  bodies)  are  introduced  into  the 
molecule  and  the  molecule  increases  in  weight,  they 
change  from  yellow  to  orange  and  so  on  through  red, 
violet,  and  blue. 

Do  you  catch  a  little  whiff  of  something  that  smells 
like  a  law  here?  The  more  we  phenylated  (i.e.,  added 
C6H5  radicals  to)  the  rosaniline  the  more  it  turned 
from  magenta  through  violet  to  a  pure  cerulean  qual- 
ity of  clear  blue.  The  same  tendency  holds  with  these 
azo  colors. 

Azo  colors  are  not  soluble  in  water,  but  are  soluble 


EVERYMAN'S   CHEMISTRY 

in  alcohol,  so  the  usual  practice  is  to  treat  them  with 
concentrated  sulphuric  acid,  thus  making  the  sul- 
phonic-acid  conjugations,  as  in  aniline  blue,  and  then 
neutralize  with  soda.  Then  they  are  soluble. 

Now  let  us  take  a  rest  for  a  minute  and  get  a  breath 
of  fresh  air.  We  have  been  trying  to  treat  of  coal-tar 
intermediates  in  an  offhand  way,  and  I'll  admit  that 
my  conscience  pricks  me  a  little.  The  subject  is  inter- 
esting, I  assure  you,  but  we  have  gone  too  fast.  The 
trouble  is,  the  only  way  to  slow  down  would  be  to 
make  the  discourse  longer,  and  that  is  just  what  we 
have  not  the  opportunity  to  do  within  the  space  of  this 
book.  The  problems  are  complex,  the  names  are  long, 
and  the  formulas  are  bewildering  save  to  those  who 
devote  their  lives  to  them.  I  have  only  indicated  a 
very  few  of  the  hundreds  of  intermediates,  and  indi- 
cated the  way  over  to  a  couple  of  color  systems,  to 
show  you  what  is  meant  by  them.  Now  let  us  address 
ourselves  to  some  of  the  best  known  colors  and  see  if 
we  cannot  achieve  greater  simplicity  in  the  effort. 

Black  is  the  most  important  color,  and  of  this  there 
are  several. 

Aniline  black  is  produced  by  the  oxidation  of  aniline 
upon  the  fiber  of  the  goods.  The  usual  method  is  to 
produce  first  what  is  called  aniline  salt  by  treating 
aniline  with  hydrochloric  acid,  and  after  treating  the 
fiber  with  this  to  oxidize  it  with  chlorate  of  potash  and 
other  oxidizing  agents.  This  is  the  old  aniline  black 
that  replaced  logwood. 

Nigrosine  is  made  by  heating  aniline  salt  with  nitro- 
benzol  until  a  pasty  mass  is  formed  which  is  dropped 
into  water.  It  is  then  sulphonated  and  neutralized 
(to  make  it  soluble)  and  dried  and  ground.  This  is 
the  black  of  shoe-blacking,  stove-polish,  etc. 

Sulphur  black.  This  involves  the  process  of  making 

332 


COAL-TAR  AND  FINISHED   PRODUCTS 


sulphur  colors,  and  just  what  the  reactions  are  it 
would  be  hard  to  say.  You  may  gather  an  armful  of 
dried  leaves  and  boil  them  up  in  a  kettle  with  sulphide 
of  sodium  and  sulphur,  and  a  brownish  vat-dye  will 
result.  So  by  treating  other  materials  with  sulphide  of 
soda  and  sulphur  you  get  dull  browns  and  yellows  and 
blues  and  greens  and  a  good  black.  They  are  very 
fast  against  washing,  but  not  very  fast  against  light. 
The  largest  use  is  for  black  cotton  stockings.  To 
make  this  black  we  must  first  produce  an  intermediate 
which  we  have  not  yet  described.  We  start  with  ben- 
zol, treat  it  with  chlorine,  and  make  chlorbenzol, 
C6H5C1.  This  is  nitrified  by  means  of  nitric  and  sul- 
phuric acids  until  we  have  dinitrochlorbenzol.  Let's 
make  the  picture: 

a 


NO, 
Dim  fro  Chlorbenzof 

Now  let  us  boil  this  with  soda  ash  (sodium  carbonate) 
and  the  chlorine  will  be  removed  and  an  OH  group  goes 
on  in  the  place  of  it.  This  gives  us  dinitrophenol,  or 


N02 
D/nifrophenoi 

333 


EVERYMAN'S   CHEMISTRY 

By  heating  this  with  sodium  sulphide  and  sul- 
phur we  get  the  required  sulphur  black  for  socks. 
But  note,  please,  how  the  cousinship  between  dye- 
stuffs  and  explosives  may  be  found  right  here.  One 
method  of  making  picric  acid — indeed,  the  method 
generally  in  vogue  in  England — is  to  follow  this  same 
process,  but  go  one  step  further  in  the  nitrification, 
so  that  trinitrochlorbenzol  is  produced. 


Tnnifrochlor  Benzo/ 
Then  oxidize  this  to 
OH 


N02 

Tnnitrophenol 
orficncAcic/ 

and  we  have  trinitrophenol,  or  picric  acid. 

Erie  Black,  or  Direct  Black,  is  the  best  black  there 
is.  It  was  developed  at  the  Schoellkopf  works  in 
Buffalo,  and  nothing  from  any  other  country  is  equal 
to  it.  It  is  made  from  H  acid,  benzidine,  meta- 

334 


COAL-TAR  AND   FINISHED  PRODUCTS 


phenylendiamine,  and  aniline.    Benzidine  is  a  curious 
thing.    If  you  start  with  azobenzene,  which  is 


N'N 


or  two  benzene  groups  hinged  together  by  two  nitro- 
gen atoms,  and  treat  this  with  zinc  dust  and  alcoholic 
potash,  you  get  hydrazobenzene,  or 


Hydrazobenzene 

Now  if  you  treat  this  with  a  strong  acid,  those  two 
benzene  rings  will  turn  somersaults,  joining  appar- 
ently by  their  other  ends  or  else  the  groups  of  NH 
will  go  to  the  ends,  where  they  will  find  another  hy- 
drogen atom: 


I  assure  you,  there  never  lived  a  chemist  yet  who 
knew  all  of  the  devious  ways  of  that  benzene  ring! 
Metaphenylendiamine  is  not  so  bad  as  it  looks.  It 
is  aniline  with  another  NH2  group  in  the  meta  posi- 


tion— 


I  do  not  know  what  the 


Mefapheny/erict/am/ne 

335 


EVERYMAN'S   CHEMISTRY 

reactions  are  that  produce  Erie  black;  they  are  very 
complicated. 

The  black  for  wool  and  silk  which  is  most  generally 
used  is  called  alpha-naphthylamine  black.  It  is  made 
by  coupling  alpha-naphthylamine,  which  you  may  re- 
member is  like  aniline  except  that  it  starts  with  naph- 
thalene instead  of  benzol  and  has  the  NH2  group  in 
the  first,  or  alpha,  position,  coupled  with  what  is  known 
as  Freund's  acid,  which  is  like  H  acid  except  that  it 
has  a  hydrogen  atom  in  the  place  of  the  OH  group. 
This  is  shaded  with  other  colors. 

Of  reds  the  most  widely  used  is  called  para  red, 


being  made  from  paranitraniline.    This 


is  diaz- 


otized  with  sodium  nitrite  (NaNO2)  and  mixed  with 
beta  naphthol.  The  coupling  takes  place  immediately, 
and  the  red  dyestuff  separates  out.  This  red  is  used 
on  bandana  handkerchiefs  and  other  cheap  cottons; 
it  is  the  red  of  wagon  paint  and  fire-engines,  barn 
doors,  and  wherever  a  fiery  red  is  wanted.  The  con- 
sumption of  it  is  enormous.  It  is  the  great  cheap  red, 
and  has  replaced  Turkey  red  or  madder  or  alizarine 
(all  the  same)  where  cheapness  rather  than  quality  is 
wanted.  It  is  not  by  any  means  as  good  a  color  for 
cotton  goods  as  alizarine. 

The  old  aniline  red  or  magenta  to  which  we  re- 
ferred a  few  pages  back  is  also  called  fuchsine,  from 
fuchsia,  and  it  is  used  on  print  cloths  and  elsewhere. 

336 


COAL-TAR  AND  FINISHED  PRODUCTS 


There  are  also  a  whole  series  of  azo  reds  used  as 
scarlets. 
Turkey  red  is  a  product  of  anthracene,  CuHio: 


The  first  step  is  to  oxidize  it  by  sodium  dichromate 
and  sulphuric  acid,  which  leaves  an  oxygen  atom  at 
positions  9  and  10  and  has  the  formula 

0 


This  is  now  treated  with  oleum  or  fuming  sulphuric 
acid  containing  50  per  cent,  sulphur  trioxide.  This 
forms  a  sulphonic  acid,  and  when  the  whole  is  fused 
with  caustic  soda  in  the  presence  of  chlorate  of  potash, 
the  SO3  group  is  removed  and  alizarine  is  formed. 
This  is  C14H602(OH)2,  or 


0 

Alizarine 
337 


EVERYMAN'S   CHEMISTRY 

This  is  the  real  old  Turkey  red,  formerly  produced 
from  the  madder  plant  and  replaced  by  this  discovery 
of  Graebe  and  Liebermann,  away  back  at  the  beginning 
of  the  'seventies.  Alizarine  is  almost  insoluble  in 
water,  and  is  only  slightly  soluble  in  alcohol.  Its 
value  as  a  dye  consists  in  its  power  to  form,  with 
metallic  oxides,  fine  colored,  insoluble  compounds 
called  " lakes."  When  cotton  is  mordanted  with  one 
of  these  oxides  it  can  be  dyed  with  alizarine  and  the 
color  depends  upon  the  oxide  used.  With  ferric  oxide 
it  is  a  violet  black,  with  chromium  oxide  claret  color, 
with  calcium  oxide  blue,  and  with  tin  and  aluminium 
oxides  it  produces  the  various  shades  of  Turkey  red. 

There  are  certain  colors,  some  of  which  are  made  with 
alizarine  as  a  base  and  some  are  not.  They  belong 
chiefly  to  the  azo  group  and  are  reduction  colors  or 
vat-dyes,  being  first  reduced  and  then  oxidized  on  the 
fiber.  They  are  the  fastest  cotton  colors  known,  and 
include  the  lighter  shades  of  reds,  yellows,  blues,  and 
greens.  The  principal  use  is  for  shirtings  and  the  like. 
They  are  referred  to  as  the  indanthrene  group  and  by 
other  names  chosen  by  different  makers.  Most  of 
them  are  still  patented. 

In  blues  the  anilines  are  still  used,  as  is  methylene 
blue,  but  larger  use  is  found  for  the  H  acid  as  benzo 
sky-blue.  In  this  H  acid  is  coupled  with  dianisidine, 
a  very  complex  body,  by  simple  coupling,  and  the  blue 
dyestuff  separates  out.  It  is  especially  used  on  silk 
and  cotton. 

Indigo  is  a  romance.  The  antiquity  of  its  use  is 
shown  in  the  fact  that  many  mummy-cloths  are  dyed 
with  it.  It  was  introduced  into  Europe  in  1516,  and 
bitter  was  the  fight  against  the  "devilish  drug"  which 
was  declared  to  spoil  fabrics  and  work  all  kinds  of 
injury  by  the  growers  of  woad,  the  rival  blue  of  those 

338 


COAL-TAR  AND  FINISHED   PRODUCTS 

days.  In  1737  its  use  was  graciously  permitted  in 
France,  and  after  that  the  other  nations  followed  suit. 

Natural  indigo  is  produced  from  a  great  series  of 
leguminous  plants  grown  in  India,  China,  and  Egypt, 
the  Philippines,  and  tropical  South  America  and 
Africa.  Over  10,000,000  pounds  of  the  dyestuff  is 
used  annually  in  the  United  States  alone.  With 
untiring  patience  the  great  A.  von  Baeyer  worked 
over  the  problems,  then  others  contributed  one  idea 
after  another,  and  when  it  was  found  that  the  start 
might  be  made  with  naphthalene  and  aniline  the 
Badische  Anilin  und  Soda  Fabrik  began  to  build. 
Before  the  first  pound  of  artificial  indigo  was  brought 
upon  the  market  in  1897  the  Badische  works  had 
expended  over  $5,000,000.  By  1911  it  had  driven  the 
use  of  natural  indigo  practically  from  the  face  of  the 
earth,  from  China  and  India  as  well  as  from  Europe 
and  America.  The  artificial  is  the  same  as  the  nat- 
ural, but  purer  and  more  reliable. 

We  shall  not  enter  into  the  process,  which  is  very 
complex  and  has  to  do  with  a  considerable  number  of 
catalytic  agents.  It  requires  vast  quantities  of  coal- 
tar  products — of  sulphuric  anhydrid  (SO3),  a  great 
deal  of  mercury,  of  chlorine,  of  ammonia,  and  of 
caustic  soda. 

It  is  a  vat-dye — that  is,  one  in  which  an  insoluble 
pigment  is  treated  with  an  alkaline  reducing  agent 
whereby  it  becomes  soluble  in  the  alkaline  bath.  As 
such  it  is  absorbed  by  the  fabric  which  is  dipped 
into  it.  Then  it  is  oxidized  by  exposure  to  the  air  and 
is  thus  reconverted  into  the  insoluble  pigment  again, 
but  now  thoroughly  absorbed  by  the  fibers. 

To  get  an  idea  of  the  situation  in  this  country,  let's 
hark  back  to  the  dyestuff  census  that  was  printed 
after  much  gnashing  of  teeth  by  the  United  States 

339 


EVERYMAN'S    CHEMISTRY 

Government  in  1916.  It  contained  a  list  of  all  the 
dyes  imported  in  1913.  There  were  a  great  many 
repetitions  in  it  because  different  makers  had  different 
names  for  similar  products.  Then,  too,  different  dyes 
were  often  mixed  together  in  Germany  to  attain  cer- 
tain shades,  and  new  names  applied  to  the  mixtures. 
The  use  of  special  labels  for  different  customers  was 
also  a  frequent  practice  among  dealers  and  agents. 

Before  the  war  there  were  five  concerns  making 
synthetic  dyestuffs  in  the  United  States.  Now,  aside 
from  twenty-three  concerns  producing  crudes  (and 
these  do  not  include  the  retort  coke-oven  plants  or 
phenol  makers),  and  sixty-eight  makers  of  the  inter- 
mediate materials,  there  are  ninety-eight  concerns 
making  finished  dyes.  They  are  not  wholly  devoted 
to  making  these  products;  some  began  to  make  cer- 
tain specialties  otherwise  unobtainable  for  their  own 
use,  and  now  they  produce  for  the  market;  others 
confine  themselves  to  one  or  two  colors,  and  still 
others  are  only  starting  up.  On  the  other  hand,  some 
are  vast  concerns,  working  intensely  with  rare  talent 
and  skill  and  rapidly  enlarging  their  capacity  and 
variety  of  product. 

Roughly  speaking,  75  per  cent,  of  the  dyestuffs 
needed  are  made  in  this  country  and  of  this  three- 
quarters  some  are  made  in  such  excess  that  a  consid- 
erable export  trade  is  carried  on  to  friendly  countries, 
especially  to  England.  Of  others  there  is  a  shortage, 
and  this  is  serious  in  such  basic  colors  as  magenta, 
methylene  blue,  auramine,  methyl  violet,  and  a  few 
more.  The  prices  of  many  of  them  are  away  up  in  the 
air,  which  has  lured  into  the  business  a  number  of 
minor  concerns  in  which  the  art  is  lacking  to  secure 
adequate  yields.  Some  also  are  under  incomplete 
chemical  control  and  fail  to  purify  their  materials 

340 


COAL-TAR  AND  FINISHED  PRODUCTS 

properly.  This  is  incidental  to  pressing  need  and 
hasty  establishment  which  the  whip  of  time  will  cor- 
rect. On  the  other  hand,  the  very  highest  praise 
should  be  awarded  to  the  conscientious  manufacturers 
who  have  strained  every  nerve  to  meet  the  country's 
needs,  often  at  the  expense  of  profit. 

We  have,  then,  three-quarters  of  the  dyestuffs 
needed,  some  a-plenty  and  others  scarce.  In  regard 
to  quality,  American-made  dyes  are  the  same  as  Ger- 
man dyes,  only  there  are  not  so  many  of  them.  If 
some  small  makers  are  still  short  in  their  yields,  the 
loss  is  theirs.  If  they  do  not  purify  their  materials 
enough,  the  defect  is  more  likely  to  be  in  shade  than 
in  fastness.  This  is  a  complete  catalogue  of  the  defects 
of  American-made  dyes  and  it  does  not  apply  to  the 
products  of  the  important  makers.  Nevertheless, 
dyers  have  been  sorely  put  to  it.  They  have  had  to 
use  one  material  when  they  wanted  another,  and  the 
substitutions  have  often  been  unhappy.  They  have 
also  been  compelled  to  relearn  the  art  of  using  dye- 
woods  for  many  purposes  which  are  new  to  the  present 
generation,  and  this  is  not  to  be  learned  in  a  day. 
The  trouble,  however,  has  principally  come  from  the 
makeshift  substitution  of  wrong  materials  for  the  right 
ones,  because  the  right  ones  are  lacking.  The  colors 
themselves  are  the  standard  articles  whether  made  in 
Germany,  France,  Switzerland,  England,  or  here. 
And  missing  and  scarce  products  are  coming  upon  the 
market  as  agreeable  surprises  at  short  intervals. 

In  regard  to  the  missing  quarter,  Congress  cut  off 
from  the  tariff  bill  the  ad  valorem  duty  on  indigo  and 
alizarine  products,  which  discouraged  manufacturers 
at  the  start.  Nevertheless,  indigo  is  now  being  made 
by  the  Dow  Chemical  Company  at  Midland,  Michi- 
gan, although  at  present  there  is  not  enough  made 

34i 


EVERYMAN'S    CHEMISTRY 

and  natural  indigo  imported  to  meet  even  the  needs  of 
the  United  States  Navy.  But  the  National  Aniline 
&  Chemical  Works,  Inc.  is  building  a  great  indigo 
plant,  and  it  is  generally  understood  that  the  Du  Pont 
Chemical  Company  is  about  to  begin,  so  that  with 
these  great  concerns  engaged  in  it,  the  production  of 
all  the  indigo  we  need  is  only  a  question  of  time.  In 
chemical  research  they  are  the  peers  of  the  great 
German  establishments. 

Alizarine  colors  are  lacking.  There  is  Turkey  red 
for  bandana  handkerchiefs,  towels,  and  print  goods, 
and  alizarine  blue,  employed  in  connection  with  indigo 
for  navy  blues  and  on  serges,  dress  goods,  and  suitings. 
Although  these  are  not  produced  yet,  the  crude  body 
from  which  they  are  made,  anthracene,  is  now  avail- 
able, and  one  or  two  of  the  largest  makers  have  the 
matter  in  hand.  It  is  merely  a  question  of  time  and 
organization. 

Fast  cotton  vat-dyes  of  the  indanthrene  type  are 
also  missing,  but  the  research  laboratories  are  busy 
and  the  outlook  is  hopeful.  A  good  wool  black  of  the 
"Diamond"  type  is  needed.  Logwood  is  now  used 
in  the  place  of  it,  and  this  is  not  fast  enough  against 
light.  There  is  also  a  shortage  of  safranines  and  the 
general  class  of  azine  colors,  including  azo  carmine  for 
red  and  pink  on  silk  and  for  printing,  which  a  large 
print  works  in  New  England  is  beginning  to  make. 
Besides  these,  there  is  wanted  a  good  developed  black 
of  the  diamine  or  diazo  type  for  a  rich,  full,  bloomy 
black  on  fine  cotton  hosiery  and  cotton-silk  goods. 
These  are  the  chief  absentees,  but  by  the  time  this  is 
printed  their  number  may  be  less. 

That  is  the  situation  at  the  end  of  three  years,  in 
August,  1917.  The  number  of  colors  produced  to-day 
or  the  number  of  dyestuffs  missing  is  not  the  important 

342 


COAL-TAR  AND    FINISHED    PRODUCTS 

fact.  In  1914  we  had  neither  crudes  nor  intermediates 
to  speak  of.  These  are  now  abundant.  We  then 
made  a  bare  one-fifth  of  our  needs  out  of  foreign 
materials;  now  we  make  three-quarters  of  those 
needed  and  some  for  export,  all  of  American  materials 
in  American  apparatus,  and  by  American  chemists. 
We  have  the  talent,  the  organizations,  the  capital, 
and  the  will.  The  men  in  the  business  are  familiar 
with  the  financial  side  of  chemical  problems;  they 
also  know  what  chemical  research  means.  The  coal- 
tar  product  industry  is  established  in  this  country  and 
it  is  here  to  stay.  The  missing  quarter  of  the  dye- 
stuffs  needed  will  soon  be  provided  and  it  looks  as 
though  only  the  odds  and  ends  would  eventually  come 
from  abroad. 

Chemical  industry  in  the  United  States  has  grown 
by  leaps  and  bounds,  but  it  lacks  co-ordination.  The 
pressure  to  produce  has  made  all  sorts  of  odd  associa- 
tions in  production.  I  know  of  a  wall-paper  manu- 
facturer who  is  making  salicylic  acid.  He  was  under 
the  necessity  of  making  some  dyes  which  he  could  not 
purchase,  and,  having  some  extra  room  and  a  live 
chemical  director,  he  took  up  this  drug  as  a  side  line. 
One  of  the  great  pulp  and  paper  companies  is  making 
chlorbenzol  and  carbon  tetrachloride  from  excess  of 
chlorine  for  bleaching,  and  also  carbon  bisulphide — 
because  a  demand  was  found  for  it.  Sulphite-pulp 
mills  are  producing  alcohol  in  increasing  quantities, 
and  a  very  large  paint-manufacturing  firm  is  one  of 
the  leading  producers  of  paranitraniline — because  they 
needed  para  red  and  could  not  buy  it.  Chemical  in- 
dustry has  not  yet  thoroughly  settled  down  in  this 
country. 

It  is  surely  a  great  deal  clearer  than  mud  that  the 
dyestuff  industry  is  only  a  part  of  the  whole.    It  is  so 
23  343 


EVERYMAN'S    CHEMISTRY 

interrelated  with  others  that  it  cannot  be  considered 
as  a  single  unit.  By  means  of  splendid  organizations 
and  much  more  intensive  scientific  application  to  the 
task  than  we  or  any  other  folk  have  been  accustomed 
to,  together  with  the  aid  of  government-owned  rail- 
ways, subsidized  steamship  lines,  the  imperial  secret 
service,  and  laws  designed  to  encourage  co-operation 
among  manufacturers,  the  Germans  built  up  almost 
a  world  monopoly  of  the  dyestuff  industry.  During 
the  three  years  of  war  no  such  machine  has  been 
established  here.  No  such  perfect  machine  could  be 
built  up  under  our  laws  and  customs.  For  instance, 
in  one  of  the  great  works  in  Germany  orthonitro- 
toluol  was  needed  as  the  starting-point  for  the  manu- 
facture of  one  of  its  leading  products.  Now  when 
toluol  is  nitrified  some  of  the  NO2  radicals  will 
take  the  ortho  position  and  some  will  go  to  the  para 
position;  but  no  amount  of  conniving  has  enabled 
chemists  so  far  to  make  orthonitrotoluol  without  pro- 
ducing at  the  same  time  some  paranitrotoluol.  The 
best  practice  yields  these  products  in  the  relation  of 
two  to  one,  respectively.  It  is  easy  to  separate  them 
after  they  have  been  made.  Now  in  this  particular 
reaction  only  the  ortho  body  was  useful;  there  was  no 
use  for  the  para  body.  What  they  did  with  the  para 
body  no  one  knew;  even  their  competitors  were  unin- 
formed. But  when  Liege  fell  the  secret  was  out.  The 
explosive  used  was  TNT,  or  trinitrotoluol,  and  if  you 
want  to  make  that  you  can  very  well  start  with  para- 
nitrotoluol, because  you  have  it  already  one-third 
nitrified.  The  next  NO2  group  will  then  take  the  ortho 
position,  and  the  third  will  hook  on  to  the  meta  posi- 
tion, for  all  TNT  is  nitrified  in  each  of  the  2,  3,  and  4, 
or  ortho,  meta,  and  para  positions.  So  for  ten  years 
or  more  that  paranitrotoluol  was  being  quietly  shipped 

344 


COAL-TAR  AND   FINISHED   PRODUCTS 

to  the  German  government  munition-works,  made  into 
TNT,  and  stored  against  the  Day  of  Wrath, 

I  do  not  offer  this  in  praise  of  German  methods.  I 
give  the  incident  merely  by  way  of  explaining  them. 

It  would  be  idle  to  try  to  report  fully  on  American 
chemical  industry  at  this  time.  It  is  not  sufficiently 
co-ordinated.  And  Congress  we  have  always  with  us, 
often  more  vindictive  than  enlightened.  It  would  be 
unjust  and  unfair  to  say  that  the  Government  of  the 
United  States  is  adverse  to  industry,  but  I  declare  it 
sometimes  seems  as  if,  at  first  sign  of  any  other  than 
a  fighting  relation  between  this  Government  and  a 
successful  industry,  the  desire  ripens  in  Congress  to 
launch  a  persecution  under  the  name  of  investigation. 
We  have  also  had  more  than  a  little  defective  chemical 
engineering.  There  has  been  a  rush  and  a  tumble,  and 
a  hurry  and  a  scurry,  and  some  men  are  not  up  to  their 
jobs.  Others  again  are  masters,  real  giants  in  mind 
and  understanding,  and  they  are  doing  things  with  a 
big  intelligence  and  with  a  steady  look  to  the  future 
that  give  one  faith  in  the  days  to  come.  American 
industry  is  launched  upon  a  chemical  career.  This 
has  taken  from  colleges  and  universities  some  of  the 
best  teachers,  while  many  young  men  have  resolved 
to  become  chemists  who  should  have  resolved  to  be- 
come almost  anything  else,  so  far  as  chemical  progress 
is  concerned.  So  we  shall  not  have  smooth  sailing. 

Without  doubt  many  small  manufacturers  will  be 
crowded  out  of  business  when  normal  times  come 
again  and  the  markets  of  the  world  are  open;  not  so 
much  because  they  are  small  as  because  when  the 
scramble  is  over  and  prices  become  competitive  their 
methods  will  prove  to  be  faulty.  On  the  other  hand, 
the  great  American  concerns  have  gone  into  chemistry 
to  stay.  The  research  laboratories  of  a  number  of 

345 


EVERYMAN'S    CHEMISTRY 

large  American  corporations  are  marvels  of  scholar- 
ship, thoroughness,  and  efficiency,  and  compare  favor- 
ably with  the  great  German  works. 

When  we  think  how  powerless  and  how  dependent 
we  were  upon  Germany  in  1914  and  how  by  the  pres- 
ent year,  1917,  American  chemists  have  met  thousands 
vof  problems  that  Germans  claimed  that  only  they 
could  solve,  how  panic  and  distress  and  closed  fac- 
tories have  given  way  to  the  industries  of  peace  as 
well  as  those  of  war  with  merely  incidental  incon- 
veniences due  to  the  closed  German  ports,  it  seems 
no  more  than  fair  to  take  off  our  hats  to  the  men  who 
have  done  these  things  and  to  give  them  their  meed  of 
praise. 

We  must  omit  discussion  of  all  sorts  of  interesting 
subjects,  because  we  have  not  the  space  and  also 
because  we  have  not  entered  into  organic  chemistry 
with  sufficient  thoroughness  to  do  so.  If  I  have 
allowed  my  enthusiasm  to  go  further  than  your  in- 
terest will  follow,  I  beg  your  pardon.  We  are,  all 
of  us,  poor  judges  of  our  own  dullness.  The  main 
thing  is  to  think  you  can  see  these  things  in  your 
mind's  eye;  the  wandering  of  atoms  and  ions  or  radi- 
cals from  one  molecule  to  another  and  shaping  them- 
selves up  into  equilibrium.  There  is  chemistry  in 
nearly  everything  that  happens,  and  if  your  chemical 
sense  is  aroused  everything  that  takes  place  becomes 
much  more  interesting.  And  if  your  curiosity  is 
quickened,  I  shall  count  myself  fortunate,  because  then 
you  may  follow  up  the  subject,  read  profound  books, 
watch  the  rushing  sap  in  growing  corn,  observe  the 
most  marvelous  of  all  chemical  processes  in  nature — 
the  synthesis  of  sugar  from  water  and  CO2  in  green 
leaves — and  maybe,  some  day,  either  you  or  some- 
body else  will  know  how  it  is  done. 

346 


APPENDIX  I 


THE    ELEMENTS 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

Al 

Aluminium 

27—3 

1  8OO-  1 

Familiar  light  metal. 
Found  in  clay,  feld- 
spar, bauxite;  very 
wide-spread.  Melts 
at  657°. 

Sb 

Antimony 

3 
1  20  —  4 

5 

1440 

Silvery-  white  solid  with 
metallic  luster.  Usu- 
ally found  with  ar- 
senic, which  it  resem- 
bles in  many  ways. 
Melts  at  629°. 

A 

Argon 

40  —  o 

-    186 

One  of  the  inert  gases 
of  the  air,  of  which  it 
forms  less  than  I  per 
cent.  Makes  no  com- 

binations. 

As 

Arsenic 

3 
75—4 

Steel-gray,  metal-like 
substance.  Poison- 

ous in  all  its  com- 

pounds. Sublimes 
without  melting  at 
about  1  00°. 

Ba 

Barium 

137—2 

A  metal  of  the  alkaline 
earths.  Something 
like  calcium.  Sul- 

phate used  as  filler 
for  paper  and  for 
paint.  Melts  at  850°. 

347 


EVERYMAN'S    CHEMISTRY 


Sym- 
bols 

Names  of 
Elements 

Approx. 

Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

Be 

Beryllium 

9—2 

Silvery  metal.     Found 

in  Beryl.   Rare.   Be- 

haves   like    magne- 

sium.    Melts  above 

960°. 

3 

Bi 

Bismuth 

20  —  4 

I42O 

Grayish-  white  solid, 

5 

lustrous,  same  fam- 

ily  as   As   and   Sb. 

Melts  at  270°. 

B 

Boron 

ii—  3 

Brown  powder.  Found 

as  boric  acid  and  a 

borate  of  sodium  or 

borax.    Does  not 

melt.      Volatilizes 

slightly    in    electric 

arc. 

i 

Br 

Bromine 

80—3 

59 

Brown  liquid.  Volatile. 

5 

One  of  the  halogens. 

7 

Cd 

Cadmium 

112  —  2 

780 

Metal    somewhat    like 

tin  and  zinc.      The 

yellow     sulphite     is 

used  as  a  pigment. 

Melts  at  320°. 

Cs 

Cassium 

I33—I 

1670 

One    of    the    alkali 

metals.     Very   rare. 

Melts  at  26°. 

Ca 

Calcium 

4O  —  2 

One  of  the  alkali  met- 

als.  Lime  is  calcium 

t 

oxide.      Very  wide- 

spread.      Melts    at 

780°. 

C 

Carbon 

12—4 

Diamond,  graphite, 

coal.     Everything 

having  life  contains 

it.     Organic  chemis- 

try is   chemistry  of 

carbon    compounds. 

Ce 

Cerium 

140—3 

Metal  of  rare  earths. 

348 


APPENDIX   I 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

4 

Used  in  gas  mantles 

and  for    striking 

sparks  on  cigar- 

lighters.     Melts    at 

623°. 

Cl 

Chlorine 

35-5—1 

-     33 

Greenish  gas.  Halogen. 

Very  wide-spread  in 

common  salt,  in 

rocks  everywhere. 

Cr 

Chromium 

52-6 

22OO 

Steel-gray  metal  used 

for  hardening  steel. 

Salts    are   used    for 

pigments.     Melts  at 

1520°. 

Co 

Cobalt 

59—3 

Hard  white  metal. 

4 

Very  like  nickel. 

Compounds  used  in 

pigments.     Melts  at 

1478°. 

Cu 

Copper 

63-5—1 

2300 

Next  to  iron  the  metal 

2 

in  greatest  use. 

Melts  at  1082°. 

Dy 

Dysprosium 

162.5—3 

Hardly  known.   Found 

in  rare  earths. 

Er 

Erbium 

167.5—3 

Hardly  known.   Found 

in  rare  earths. 

Eu 

Europium 

152—3 

Hardly  known.   Found 

in  rare  earths. 

F 

Fluorine 

I9—I 

-    I87 

Greenish-yellow  gas. 

One  of  the  halogens. 

Found  in  fluorspar 

and  other  rocks. 

Gd 

Gadolinium 

157—3 

Hardly  known.   Found 

in  rare  earths. 

Ga 

Gallium 

70—3 

Rare  metal  something 

like  Al. 

Ge 

Germanium 

72—2 

Very  rare  metal  found 

4 

sometimes   with   Ag 

and  Pb. 

Au 

Gold 

197—1 

2530 

Almost  more  important 

3 

socially    than    it    is 

349 


EVERYMAN'S    CHEMISTRY 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

chemically.  Melts  at 

1064°. 

He 

Helium 

4—0 

-      27 

Companion  of  argon. 

Spectroscope    shows 

it  in  photosphere  of 

the  sun.    Also  found 

occluded  in  rocks. 

Ho 

Holmium 

163.5—0 

Hardly  known. 

H 

Hydrogen 

i  —  i 

-    152 

Lightest    gas.       Two- 

thirds  by  volume  of 

water.    The  business 

end  of  all  acids,  and, 

with  oxygen,  the 

business  end   of 

bases. 

In 

Indium 

US—  3 

Rare    metal.        Same 

group  as  Ga. 

I 

Iodine 

127—1 

184 

Violet-black  solid. 

Found  in   sea-water 

and  marine  products. 

Heaviest  of  the  halo- 

gens. 

2 

Ir 

Indium 

193—3 

Grayish  -  white  metal, 

7 

very   like   platinum. 

Melts  at  about  2000°. 

2 

Fe 

Iron 

56-3 

2240 

The  metal  in  greatest 

use.    Melts  at  1530°. 

Kr 

Krypton 

83—0 

-     152 

An  inert  gas  of  the  air 

present  to  the  extent 

of  0.00005  volumes  in 

1,000. 

La 

Lanthanum 

139—3 

Another  element  found 

in  the  rare  earths. 

Pb 

Lead 

2O9  —  2 

1525 

Gray  metal  usually 

4 

found    as    sulphide. 

Poisonous  in  all  com- 

binations.      Widely 

used.   Melts  at  326°. 

Li 

Lithium 

7—2 

1400 

An   alkali   metal,   like 

350 


APPENDIX   I 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

sodium    and    potas- 

sium. The  lightest  of 

metals.       Melts     at 

186°. 

Lu 

Lutecium 

174—3 

Found  in  rare  earths. 

Mg 

Magnesium 

24—2 

1  120 

A   very   light,    silvery 

metal,     that    would 

be  largely  used  for  its 

mechanical  qualities 

if     it     were     cheap 

enough.       Melts   at 

632°. 

2 

3 

Mn 

Manganese 

55—4 

1900 

A  gray  metal,  harder 

6 

than    iron,    used    in 

7 

iron  and  steel  indus- 

try.   Melts  at  1245°. 

Hg 

Mercury 

200  —  i 

357 

Silvery    liquid.       Dis- 

2 

solves  and   forms 

amalgams  with  many 

metals.    Solidifies  at 

-39°. 

2 

3 

Mo 

Molybdenum 

96—4 

Black   metal  alloyed 

5 

with   steel   to  make 

6 

"high  speed"  tools. 

Mo   compounds  are 

used  in  pigments. 

Nd 

Neodymium 

144— 

Little    known    of    it. 

Found  in  rare  earths. 

Ne 

Neon 

20  —  O 

-  233 

Inert  gas  of  air.    0.015 

parts  per  1,000  of  it 

in  atmosphere. 

Ni 

Nickel 

59—2 

Silvery  metal,  first  cou- 

sin to  cobalt.    Used 

for  alloying  steel  and 

for  nickel-plating. 

Melts  at  1452°. 

351 


EVERYMAN'S    CHEMISTRY 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

3 

Cb 

Niobium 

59—5 

Rare  metal  found  with 

tantalum.    Formerly 

called   columbium, 

whence   the   symbol 

Cb.    Melts  at  1720°. 

Nt 

Niton 

222  — 

Name  given  to  radium 

emanation. 

N 

Nitrogen 

14—3 

-    194 

Gas    comprising    four- 

5 

fifths  of  air.  Hard  to 

get    into     combina- 

tion, but  when  this  is 

achieved  it  becomes 

very  lively. 

2 

Os 

Osmium 

I9I—4 

Like  indium,  one  of  the 

6 

platinum   metals. 

Melts  at  about  2  300°. 

0 

Oxygen 

1  6—  2 

-    182 

Gas    comprising    one- 

fifth  of  the  air.    The 

old  Jupiter  Maximus 

of  chemistry. 

2 

Pd 

Palladium 

1  06  —  4 

Another  rare  metal  of 

6 

the  platinum  family. 

Melts  at  1549°. 

P 

Phosphorus 

31—3 

290 

Poisonous  white  waxy 

5 

substance,    very   in- 

flammable, and    an 

, 

amorphous    brown 

powder.  Widespread 

in  rocks    and  living 

things.  Melts  at  44°. 

2 

Pt 

Platinum 

195—4 

2450 

Harder  than  silver  or 

6 

gold.   Does  not  com- 

bine easily  with  oxy- 

gen  or   with   acids. 

Melts  at  1753°. 

K 

Potassium 

39—1 

700 

Alkali   metal,   whitish, 

wax-like    substance. 

352 


APPENDIX   I 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

N, 

Highly  inflammable; 

very  wide-spread. 

Melts  at  62°. 

Pr 

Praseodymium 

140—3 

Of  the  rare-earth  series. 

Ra 

Radium 

226  —  2 

White  metal  that  turns 

black  in  air.  Exceed- 

ingly rare,  radio-ac- 

tive.  Melts  at  about 

700°. 

Rh 

Rhodium 

103— 

A   rare   metal   of   the 

platinum  group. 

Melts  at  1650°. 

Rb 

Rubidium 

85—1 

696 

A  rare  alkali  metal  sim- 

ilar to  caesium.  Melts 

at  38°. 

Ru 

Ruthenium 

I  O2  — 

A   rare   metal   of   the 

platinum   group. 

Melts  at  about  2000°. 

Sm 

Samarium 

150— 

Of  the  rare-earth  series. 

Sc 

Scandium 

44—3 

Very  rare.    Something 

like  Al. 

2 

Se 

Selenium 

79—4 

688 

Gray,  metal-like,  solid, 

6 

and  amorphous 

brown   powder. 

Found  associated 

with   sulphur.     Has 

properties  of  metal. 

Conductivity  of  elec- 

tricity is  increased  in 

the  light.     Melts  at 

170-217°. 

Si 

Silicon 

28-4 

about 

A  brown  powder  and 

3000 

dark  -  gray  crystals. 

Constitutes  one- 

fourth  of  the  earth. 

With  O  it  is  sand. 

Melts  at  1500°. 

Ag 

Silver 

108  —  i 

about 

White    metal     known 

„ 

1350 

since  prehistoric 

times.     Conducts 

353 


EVERYMAN'S    CHEMISTRY 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

heat  and  electricity 

better  than  copper. 

Melts  at  962°. 

Na 

Sodium 

123  —  I 

877 

Alkali  metal.    Consist- 

ency of  cheese.   Oxi- 

dizes on  exposure  to 

air.  Part  of  common 

salt  and  very  wide- 

spread. Melts  at  97°. 

Sr 

Strontium 

87-5—2 

One    of    the    alkaline 

earth     metals     with 

calcium  and  barium. 

Sr   compounds   pro- 

duce red  flames;  used 

for  Greek  fire.  Melts 

at  800°. 

S 

Sulphur 

32—2 

448 

Amorphous  yellow 

4 

powder,  yellow  crys- 

6 

tals,     brown,     solid 

and   other  forms. 

Very  wide-spread. 

Melts  at  103°. 

Ta 

Tantalum 

181  —  4 

Gray  metal  found  usu- 

5 

ally    with    niobium. 

Used  for  electric 

lamp   filaments. 

Melts  at  about  2850°. 

Te 

Tellurium 

127—2 

1390 

Silver-gray  with  metal- 

4 

lic  luster.   Similar  to 

selenium.     Melts  at 

453°. 

Tb 

Terbium 

159—0 

Metal   of    the   rare 

earths 

Tl 

Thallium 

204  —  i 

Metal,    rare,   like  gal- 

2 

lium  and  indium. 

Th 

Thorium 

232—3 

Metal  of    rare  earths. 

4 

Used    for    incandes- 

cent gas  mantles  with 

5  per  cent,  of  cerium. 

Melting-point    very 

high. 

354 


APPENDIX   I 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

Tm 

Thulium 

168— 

Metal   of  the  rare 

earths. 

Sn 

Tin 

Il8  —  2 

2275 

Ore  widely  distributed 

4 

but     not     plentiful. 

One     of     the     very 

trickiest    of    metals. 

Melts  at  231°. 

2 

Ti 

Titanium 

48—6 

Found    nearly    every- 

where in   minute 

quantities.     Alloyed 

with  steel  to  increase 

toughness.    Melts 

at  1795°. 

2 

4 

W 

Tungsten 

184—5 

Like  molybdenum. 

6 

Uses:    electric  -  light 

filament  for  the  met- 

al  and   solutions  of 

compounds  render 

cotton  and  other  fab- 

rics    slow     burning. 

Melts  at  about  2450°. 

3 

4 

U 

Uranium 

238—5 

Related  to  molyb- 

6 

denum  and  tung- 

sten.    Compounds 

are  used  for  making 

fluorescent   glass. 

Melts     at    about 

1500°. 

2 

V 

Vanadium 

51—3 

Silvery  metal.  Head  of 

4 

vanadium  family 

5 

which  includes  niobi- 

um   and    tantalum. 

Increases      hardness 

and    malleability   of 

steel.  Melts  at  1  720°. 

355 


EVERYMAN'S   CHEMISTRY 


Sym- 
bols 

Names  of 
Elements 

Approx. 
Atomic  Wt. 
and 
Valence 

Boiling- 
points  in 
Degrees 
Centigrade 

Description 

X 

Xenon 

130  —  o 

-    109 

Inert  gas.    1,000  parts 

air  contain  0.000006 

parts  X. 

Yb 

Ytterbium 

172—3 

Very  rare.    Same  fam- 

ily as  scandium,  lan- 

thanum,   and   yttri- 

um.   Related  to  Al. 

Y 

Yttrium 

89—3 

See  Ytterbium. 

Zn 

Zinc 

65—2 

916 

Bluish  -  white     metal. 

Almost  as  tricky  as 

tin.  Melts  at  41  8°. 

Zr 

Zirconium 

90—4 

Rare  -  earth    metal. 

Used   with   thorium 

and  cerium.  Melting- 

point  very  high. 

In  chemical  compounds  the  symbol  of  an  element 
indicates  an  atom  of  it.  If  there  is  more  than  one 
atom  of  any  one  element  to  be  indicated,  a  small  figure 
at  the  lower  right  of  the  symbol  is  used. 

The  valence  of  an  element  is  the  number  of  bonds  or 
hyphens  with  which  an  atom  of  it  is  found  combined 
with  those  of  other  elements  in  molecules.  This  is 
not  usually  indicated  by  any  special  sign. 

A  formula  indicates  a  single  molecule.  Thus  a  mole- 
cule of  water  is  composed  of  two  atoms  of  hydrogen 
and  one  atom  of  oxygen.  It  is  written  H^O.  Two 
molecules  would  be  2H2O,  and  five  molecules  5H2O. 
Since  hydrogen  is  univalent — that  is,  since  it  has  but 
one  bond  or  hook  or  hyphen  for  combining,  the  formula 
shows  that  oxygen  is  attached  to  it  in  water  with  two 
bonds.  A  more  graphic  way  of  writing  the  formula 
for  water  would  be  H — 0 — H. 

A  chemical  equation  indicates  a  chemical  process 

356 


APPENDIX   I 

and  shows  the  changes  in  molecules.     For  instance, 
so3  +  H2o  =  H2so4 

means  that  one  molecule  of  sulphur  trioxide  combines 
with  one  molecule  of  water  to  produce  one  molecule  of 
sulphuric  acid. 

The  metric  system  of  weights  and  measures  is  in 
universal  use  in  scientific  work,  and  unless  special 
mention  is  made  the  centigrade  thermometer  is  indi- 
cated in  all  records  of  temperature.  It  is  easy  to 
change  centigrade  to  Fahrenheit  by  multiplying  the 
number  of  degrees  centigrade  by  1.8  and  adding  32. 
To  change  Fahrenheit  to  centigrade,  deduct  32  and 
divide  the  remainder  by  1.8. 


APPENDIX    II 

BIBLIOGRAPHY 

VERY  popular  and  not  at  all  technical  are  the 
delightful  books  of  the  late  Robert  Kennedy 
Duncan:  The  New  Knowledge,  published  by  the  A.  S. 
Barnes  Company,  of  New  York,  and  Some  Chemical 
Problems  of  Today,  and  The  Chemistry  of  Commerce, 
both  published  by  Harper  &  Brothers.  Another  ex- 
cellent book,  easy  to  read  and  which  requires  no  pre- 
vious chemical  knowledge,  is  Samuel  T.  Sadtler's 
Chemistry  of  Familiar  Things,  published  by  J.  B.  Lip- 
pincott  &  Co.,  of  Philadelphia.  Geoffrey  Martin's 
Triumphs  and  Wonders  of  Modern  Chemistry,  and  his 
Modern  Chemistry  and  Its  Wonders  (D.  Van  Nostrand 
Company,  New  York),  are  also  interesting.  The 
chemical  world  is  so  vast  that  these  popular  treatises 
hardly  overlap  one  another  in  subject. 

I  have  attempted  to  go  deeper  into  the  chemical 
aspect  of  things  than  is  usual  in  popular  books,  in  the 
hope  that  you  may  be  persuaded  to  go  on  with  the 
subject  after  you  have  had  your  turn  with  me.  If 
you  do,  and  want  to  begin  with  a  short  text-book, 
there  is  a  good  one  designed  for  high  schools  called 
Chemistry  of  Common  Things,  by  Brownlee,  Fuller, 
Hancock,  and  Whit  sit,  four  high-school  teachers  of 
chemistry,  that  is  very  well  arranged.  Allyn  &  Bacon, 
of  New  York,  publish  it.  It  is  a  good  book  to  start 
with,  but  of  course  it  is  not  comprehensive.  If  you 
24  359 


EVERYMAN'S    CHEMISTRY 

want  to  get  right  into  the  heart  of  the  thing,  I  recom- 
mend Modern  Inorganic  Chemistry,  by  J.  W.  Mellor, 
published  by  Longmans,  Green  &  Co.,  New  York,  or 
Alexander  Smith's  Inorganic  Chemistry,  brought  out 
by  the  Century  Company.  I  could  make  a  much 
longer  list,  but  these  are  both  good  books.  In  the 
organic  field  I  like  Bernthsen's  Organic  Chemistry 
(D.  Van  Nostrand  Company,  New  York)  and  Lessar 
Cohen's  Practical  Organic  Chemistry  (Macmillan  Com- 
pany). Another  good  one  to  start  with  is  Principles 
of  Organic  Chemistry,  by  J.  F.  Norris  (McGraw-Hill 
Book  Company).  A  good  introduction  to  physical 
chemistry  is  found  in  the  first  volume  (Theoretical 
Part)  of  Qualitative  Chemical  Analysis,  by  Julius 
Stieglitz  (Century  Company).  This  leads  along  into 
the  modern  theories  of  solutions;  but  while  the  solu- 
tions are  usually  dilute,  the  book  is  rather  concen- 
trated. It  is  a  beautiful  work,  but  it  was  not  meant 
to  while  away  an  idle  hour.  On  colloid  chemistry 
there  is  Colloids  and  the  Ultra  Microscope,  by  R.  A. 
Zsigmondy,  translated  by  Jerome  Alexander  (John 
Wiley  &  Sons,  New  York),  and  The  Chemistry  of 
Colloids,  by  W.  W.  Taylor  (Longmans,  Green  &  Co.). 
In  regard  to  radium  and  radio  activity,  going  more 
profoundly  into  the  subject  than  did  Doctor  Duncan 
in  his  New  Knowledge,  there  are  two  good  works  by 
Ernest  Rutherford — one  called  Radio  Activity,  and 
published  by  G.  P.  Putnam's  Sons,  and  the  other 
Radio  Active  Transformation,  bearing  the  imprint  of 
Charles  Scribner's  Sons. 

The  practical  man,  however,  knows  very  well  that 
he  cannot  get  the  whole  theory  of  chemistry  into  his 
head  by  a  twist  o'  the  wrist,  and  he  is  likely  to  be 
anxious  to  get  at  the  books  written  on  the  subjects  in 
which  he  is  already  interested  with  a  view  to  under- 

360 


APPENDIX  II 

standing  as  much  as  he  can.  A  good  general  survey 
of  the  industrial  field  may  be  obtained  from  Allen 
Rogers's  Manual  of  Industrial  Chemistry  (Van  Nos- 
trand).  A  new  edition  will  appear  about  the  time 
the  present  work  is  issued.  A  shorter  book  is  Indus- 
trial Chemistry  for  Engineering  Students,  by  H.  H. 
Benson  (Macmillan).  The  following  more  or  less 
technical  works  (some  being  more  and  others  less) 
are  standard: 

Water  Supply,  by  W.  P.  Mason.  Price,  $4.  John 
Wiley  &  Sons,  New  York.  Glass  Manufacture,  by 
Walter  Rosenhain.  $2.  D.  Van  Nostrand  Com- 
pany, New  York.  A  Treatise  on  Ceramic  Industries, 
by  E.  Bourry ;  translated  by  A.  B.  Searle.  Scott  Green- 
wood &  Son,  London.  History  of  the  Clay  Working 
Industry  in  the  United  States,  by  Rees  &  Leighton. 
$2.50.  John  Wiley  &  Sons,  New  York.  Clays  (more 
comprehensive  but  more  technical  than  the  above), 
by  H.  Rees.  $5.  John  Wiley  &  Sons,  New  York. 
The  Chemistry  and  Testing  of  Cement,  by  C.  H.  Desch. 
Edward  Arnold,  London.  Portland  Cement,  by  Rich- 
ard K.  Mead.  Chemical  Publishing  Company,  Easton, 
Pennsylvania.  Sulphuric  Acid  and  Alkali,  by  George 
Lunge.  D.  Van  Nostrand  Company,  New  York. 
Coal-Tar  and  Ammonia,  by  George  Lunge.  D.  Van 
Nostrand  Company,  New  York.  Principles  of  Metal- 
lurgy, by  C.  H.  Fulton.  McGraw-Hill  Book  Company, 
New  York.  Metallurgy,  by  Herbert  Lang.  McGraw- 
Hill  Book  Company,  New  York.  Handbook  of  Metal- 
lurgy, by  Schnabel  &  Lewis.  2  volumes.  Macmillan 
Company,  New  York.  Metallic  Alloys,  by  G.  H. 
Gulliver.  Clark  Griffin  &  Co.,  London.  The  Metal- 
lurgy of  Iron  and  Steel,  by  Bradley  St  ought  on. 
McGraw-Hill  Book  Company,  New  York.  Principles 
of  Copper  Smelting,  by  Edward  Dyer  Peters.  Mc- 

361 


EVERYMAN'S    CHEMISTRY 

Graw-Hill  Book  Company,  New  York.  Practice  of 
Copper  Smelting,  by  Edward  Dyer  Peters.  McGraw- 
Hill  Book  Company,  New  York.  Metallurgy  of  Lead, 
by  H.  O.  Hofman.  McGraw-Hill  Book  Company, 
New  York.  Metallurgy  of  Tin,  by  Henry  Louis.  Mc- 
Graw-Hill Book  Company,  New  York.  Production 
and  Properties  of  Zinc  and  Cadmium,  by  W.  R.  Ingalls. 
$3.  McGraw-Hill  Book  Company,  New  York.  Metal- 
lurgy of  Zinc  and  Cadmium,  by  W.  R.  Ingalls.  $6. 
McGraw-Hill  Book  Company,  New  York.  Nitro- 
cellulose Industry,  by  E.  C.  Wooden.  2  volumes. 
(Covers  entire  field  from  artificial  silk  and  leather  to 
celluloid  and  smokeless  powder.)  D.  Van  Nostrand 
Company,  New  York.  Explosives,  by  Arthur  Mar- 
shall. P.  Blackiston's  Son  Company,  Philadelphia. 
Explosives,  by  H.  Brunswig;  translated  by  Munroe 
and  Kibler.  John  Wiley  &  Sons,  New  York.  Ameri- 
can Petroleum  Industry,  by  Bacon  and  Hamor.  $10. 
2  volumes.  (New,  complete,  standard  work  on  sub- 
ject.) McGraw-Hill  Book  Company,  New  York. 
Industrial  Alcohol,  by  J.  D.  Mclntosh.  Scott  Green- 
wood &  Son,  London.  Hydrogenation  of  Oils,  by  Carl- 
ton  Ellis.  D.  Van  Nostrand  Company,  New  York. 
Oils,  Fats,  and  Waxes,  by  J.  Lewkowitsch.  3  volumes. 
5th  edition.  Macmillan  Company,  New  York. 


INDEX 


Absolute  Zero,  25. 

Acetaldehyde,  251. 

Acetic  Acid,  251,  254. 

Acetone,  266. 

Acety cellulose,  251,  304. 

Acheson,  Edward  G.,  134,  222. 

Acid  Phosphate,  in. 

Soils,  32. 
Acids,  45,  87. 
Acrylic  Acid,  256. 
Actinic  Rays,  76. 
Adsorption,  32. 
Affinity,  43. 
Air  and  Water,  59. 

Compressed,  69. 

Pressure,  25. 
Alabaster,  155. 
Alcohols  and  some  Relatives,  258. 

List  of,  258. 

Aldehydes  and  Ketones,  265. 
Aldoses,  283. 
Ale,  260. 

Alexander,  Jerome,  32,  35. 
Aliphatic  Compounds,  236. 
Alizarine,  337. 
Alkali  Deserts,  106. 

Metals,  117. 
Alkalies,  45,  50. 
Allotropic  Modifications,  95. 
Allotropy,  95. 
Allylene,  248. 
Alpha  Naphthol,  328. 
»       Naphthylamine  Black,  336. 
Alum,  142. 
Alumina,  141. 
Aluminates,  141. 
Aluminium,  141,  347. 

Bronze,  181. 

Chloride,  142. 

Hydroxide,  141. 


Aluminium,  Oxide,  141. 

Silicate,  142. 

Sulphate,  142. 
Aluminum,  141. 
Amines,  312. 
Ammonia,  82,  85. 
Ammonium  Fluoride,  90. 

Hydroxide,  86. 

Sulphate,  229. 
Anhydrids,  48. 
Aniline,  321,  326. 

Black,  332. 

Blues,  331. 
Animal  Black,  224. 
Annatto,  275. 
Anthracene,  317,  323,  337. 
Anthracite,  225. 
Antimony,  115,  347. 

Sulphide,  115. 
Appendix,  347. 

Apple-tree,  The  bottle-fed,  127. 
Aquadag,  223. 
Argenite,  203. 
Argon,  44,  347. 
Aromatic  Bodies,  237. 

Compounds,  315. 
Arsenic,  113,  347. 
Arsenious  Oxide,  114. 
Arsine,  113. 
Asbestos,   161. 

Platinized,  104. 
Atoms,  17. 

Automobile  Fuels,  241. 
Avogadro's  Law,  21. 
Azobenzene,  335. 
Azo  Colors,  331. 
Azurite,  1 80. 


B 

Babbitt  Metal,  115. 
Bacon,  Raymond  F.,  3. 


363 


EVERYMAN'S   CHEMISTRY 


Bakelite,  266. 

Ball  Clay,  144. 

Bancroft,  Wilder  DM  31,  35. 

Barium,  347. 

Barley  Sugar,  281. 

Barrett's  Disinfecting  Fluid,  184. 

Bases,  45,  87. 

Baskerville,  Charles,  94,  270. 

Bauxite,  141. 

Beehive  Coke  Ovens,  224. 

Beer,  259. 

Beet  Sugar,  286. 

Benzidine,  335. 

Benzine,  Petroleum,  294. 

Benzoic  Acid,  322.' 

Benzol,  315. 

or  Benzene,  316. 

Ring,  Positions  in  the,  321. 
Benzo  Sky  Blue,  338. 
Berkeley,  Bishop,  21. 
Beryllium,  348. 
Bessemer  Converter,  169. 

Sir  Henry,  169. 

Steel,  169. 

Beta  Naphthol,  328. 
Bibliography,  359. 
Birkeland  and  Eyde,  80. 
Bismuth,  116,  179,  348. 

Subnitrate,  116. 
Bituminous  Coal,  226. 
Black  Copper,  176. 
Blast  Furnace  Gases,  167. 
Blaugas,  243. 
Bleaching,  92,  153. 

Powder,  121,  152. 
Blood,  Heat  of,  61. 
Blue  Ware,  214. 

Vitriol,  179. 
Boiler  Scale,  72. 
Boneblack,  224. 
Boracic  Acid,  147. 
Borax,  147. 
Boric  Acid,  147. 

Oxide,   147. 
Boron,  146,  348. 
Bradley,  Charles  S.,  80. 
Brandy,  260. 
Brass,  180,  183. 
Bread-making,  299. 
Breakfast  Cocoa,  291. 
Brick,  143. 
Britannia  Metal,  115. 


Bromine,  88,  94,  348. 
Bronze,  180. 

Brownian  Movement,  33,  35. 
Bucher,  John  E.,  85. 
Burnt  Sienna,  199. 
Burton,  W.  M.,  242. 
Butadiene,  252. 
Butane,  235,  237. 
Butyric  Acid,  254. 
By-product  Coke  Ovens,  224. 


Cadmium,  348. 
Caesium,  129,  348. 
Calcareous  Marl,  162. 
Calcite,  161. 
Calcium,  148,  348. 

Carbide,  83,  153. 

Chloride,  91,  151. 

Cyanamide,  83,  154. 

Halogen  Compounds,  149. 

Hydride,   149. 

Hydroxide,  149,  151. 

Hypochlorite,  152. 

Nitride,  149. 

Oxide,  149. 

Phosphate,  146. 

Phosphide,  154. 

Silicate,  148. 

Sulphate,  91,  148. 

Sulphide,   154. 

Tungstate,  202. 
Calcspar,  161. 
Calomel,  215. 
Candy,  289. 
Cane  Sugar,  286. 
Carbide  of  Calcium,  83. 
Carbohydrates,  284. 
Carbolic  Acid,  327. 
Carbon,  219,  348. 

Amorphous,  223. 

Bisulphide,  232. 

Compounds,  52. 

Dioxide,  47,  59,  231. 

Electrodes,  222. 

Monoxide,  230. 

Tetrachloride,  97,  231. 
Carbonic  Acid,  2,  47. 

Acid  Gas,  231. 
Carborundum,  134. 
Carbylamines,  313. 


364 


INDEX 


Casing  Head  Gasolene,  239. 

Cassiterite,  185. 

Castor-oil,  271. 

Catalyst,  51. 

Catalysis,  50. 

Caustic  Soda,  118,  119. 

Cellulose,  284,  303. 

and     Nitrogen    Compounds, 

303- 

Natural  Production  of,  209. 
Cement,  155. 

Clinker,  157. 

from  Slag,  157. 

Natural,  156. 

Rock,  156. 

Centigrade  and  Fahrenheit,  357. 
Cerium,  348. 
Chalk,  149,  162. 
Chamber  Acid,  102. 
Champagne,  260. 
Charcoal,  223. 
Chemical  Affinity,  43. 

Control,  8. 

Enterprises,  13. 

Equations,  356. 

Miseries,  3. 

Names  and  Phrases,  54. 

National  Bank,  106. 


Chlorophyl,  208. 
Chocolate,  291. 

Cream  Drops,  291. 
Chrome  Green,  199. 

Nickel  Steel,  199. 

Ocher,  197. 

Steel,  73- 

Tanning,  200. 

Yellow,  199. 
Chromite  of  Iron,  197. 
Chromium,  197,  349. 

Oxides,  199. 
Cinnabar,  97,  214. 
Clarke,  F.  W.,  41. 
Clay,  142. 

Colloidal,  142. 

Clays,  Various  Kinds  of,  144. 
Coagulation,  33. 
Coal  Gas,  227,  319. 

Low  Grade,  230. 

Powdered,  226. 

Products,  319. 

Tar  Crudes,  324. 

Tar  Intermediates,  320. 

Tar  Intermediates  and  Fin- 
ished Products,  326. 
Cobalt,  196,  349. 

Oxide,  197. 


Chemistry   of    Common    Things,  Cobaltous  Chloride,  196. 

119.  Cocoa  Beans,  291. 

of  Familiar  Things,  68.  Butter,  277,  291. 

Chemists'  Club,  131.  Cocoanut  Oil,  272. 

Club  Employment  Bureau,  7.  Coke,  224,  319. 


Chewing  Gum,  292. 

Chicle,  292. 

Chile,  Nitrate  Beds  of,  79. 

Saltpeter,  117. 
China  Clay,  144. 

Wood  Oil,  296. 
Chinese  Vegetable  Tallow,  272. 

White,  183. 
Chlorbenzol,  316. 
Chloride  of  Lime,  152. 

and  Sanitation,  94. 
Chlorination  of  Water  Supplies, 

93- 

Chlorine,  76,  88,  349. 

and  Oxygen,  92. 

as  a  Disinfectant,  93. 

Dioxide,  93. 

Monoxide,  92. 
Chloroform,  245,  266. 


Cold,  44. 

Colgan,  Mr.,  292. 
Cohoe,  Wallace  G.,  305. 
Collodion,  304. 
Colloid  Chemistry,  30. 
Conerite,   158. 
Copper,  176,  349. 

Alloys,   1 80. 

Matte,  178. 

Pyrites,  97. 

Refining,  178. 

Silicide,  180. 

Smelting,  177,  178. 

Steel,  173. 

Sulphate,  179. 

Sulphides,  178. 
Corrosive  Sublimate,  215. 
Corundum,  142. 
Cotton-seed  Oil,  271. 

365 


EVERYMAN'S    CHEMISTRY 


Cottrell,   Frederick  Gardner,   64,    Electrons,  20. 


167,  178. 
Cottrell  Process,  34. 
Cracking  Petroleum,  241. 
Crehore,  Albert  C.,  20. 
Crucible  Steel,  170. 
Crude  Petroleum,  239. 
Cryolite,  118. 
Cullett,  138. 
Cuprammonium,  177. 
Cupric  Chloride,  179. 

Oxide,  176. 
Cuprosilicon,  180. 
Cuprous  Chloride,  1 79. 

Oxide,  176. 

Cushman,  Allerton  S.,  32. 
Cyanogen,  231. 

D 

Denatured  Alcohol,  261. 
Dextrose,  283. 
Diamond,  219. 
Diamonds,  Artificial,  220. 
Diatomaceous  Earth,  134. 
Diazonium  Group,  331. 
Dicalcium  Silicate,  156. 
Dichlormethane,  215. 
Dimethylamine,  312. 
Dinitrochlorbenzol,  333. 
Dinitrophenol,  333. 
Dissociation,  27. 
Dolomite,  148,  162. 
Dr.  Jekyll  and  Mr.  Hyde,  95. 
Duncan,  Robert  Kennedy,  40,  300. 
Dunderhead  Mfg.  Co.,  8. 


Electroplating,  29. 
Elements  and  their  Compounds, 
38. 

Descriptive  List,  347. 

in  Life,  41. 
Emery,  142. 
Employment    Bureau,    Chemists' 

Club,  7. 
Erbium,  349. 
Erie  Black,  336. 
Esparto,  311. 
Esters  and  Ethers,  263. 
Ethane,  237,  250. 
Ethyl  Alcohol,  259. 

Aldehyde,  265. 
Ethylene  Chlorides,  251. 

Dichloride,  243. 

Glycol,  244. 
Europium,  349. 
Explosives,  87. 
Export  Oil,  239. 


Fahrenheit  into  Centigrade,  357. 
Fast  Cotton  Vat  Dyes,  338. 
Fats  and  Oils,  256 

Oils  and  their  Products,  266. 
Fatty  Acids,  253. 

List  of,  255. 
Fatwad,  Mr.,  16. 
Feldspar,  145. 
Ferric  and  Ferrous  Compounds, 


Dust,  63. 

Dutch  Metal,  180. 

Dyestuff     Situation     in 

States,  339. 
Dyestuffs,  324. 
Dynamite,  87,  263. 
Dysprosium,  349. 


Electric  Dog,  108. 

Precipitation,  65. 

Steel  Furnaces,  171. 
Electrochemistry,  29. 
Electrolytes,  26. 
Electrolytic  Refining,  29. 


163. 

Oxide,  163. 
Ferrochromium,  199. 
Ferromanganese,  201. 
United   Ferrous  Sulphate,  174. 
Firebrick,  143. 
Fire  Clay,  144. 
Fischer,  Emil,  285,  513. 
Fish  Oil,  271. 
Flotation,  177. 
Fluorine,  88,  89,  90,  349. 
Fink  Colin,  G.,  35. 
Fog  at  Sea,  67. 
Formaldehyde,  265. 
Formic  Acid,  253. 
Formulas,  356. 
Frank  &  Caro,  83. 
Franklinite,  182. 
366 


INDEX 


Frasch,  Herman,  96. 
Freezing  Machines,  64. 
Freund's  Acid,  336. 
Fructose,  283. 
Fruit  Sugar,  283. 
Fuchsine,  336. 
Fuels,  Gaseous,  227. 

Liquid,  227. 
Fuller's  Earth,  146. 


Gadolinium,  349. 
Galactose,  284. 
Galena,  188. 
Galenite,  188. 
Gallic  Acid,  322. 
Gallium,  349. 
Galvanized  Iron,  182. 
Gans,  Robert,  73. 
Gas  Engines,  226. 

Liquor,  319. 

Natural,  229. 

Standards,  229. 

Statistics   in   United   States, 

230. 

Gaseous  Fuels,  227. 
Gases,  21,  24. 
Gasolene  Test,  240. 
Gayley,  James,  166. 

Process,  166. 
Gay-Lussac  Tower,  102. 
German  Industrial  Chemistry,  343. 

Silver,  180. 
Germanium,  349. 
Gin,  260. 
Glass,  134. 

Baking  Dishes,  137. 

Bottles,  139. 

Building,  138. 

Colored,  138. 

Cut,   136. 

Etching,  90. 

Fluxes,  135. 

Gall,  138. 

Kitchenware,  137. 

Laboratory,  136. 

Red,  1 08. 

Various  Kinds,  137. 
Glassmaking,  The  Art  of,  138. 
Glauber's  Salt,  117. 
Glazes,  144. 


Glover  Tower,  101. 
Glucose,  283. 

Wholesomeness  of,  289. 
Glycerides,  263. 
Glycerin,  252. 
Glycerol,  261. 
Glycogen,  298. 
Glycol  and  Glycerin,  271. 
Gold,  210,  349. 

Amalgamation  Process,  211. 

Chlorination  Process,  211. 

Colloidal,  212. 

Color  of,  210. 

Cyanide  Process,  211. 

Faraday's,  212. 

Production  of,  212. 

Sodium  Cyanide  Process,  212, 

Solvent  for,  211. 

Washing,  211. 
Goldschmidt,  Hans,  197. 

Process,  197,  201. 
Graebe  and  Liebermann,  338. 
Grain  Alcohol,  259. 
Grape  Sugar,  283. 
Graphite,  221. 

Deflocculated,  222. 

in  Iron,  167. 
Graphitic  Acid,  221. 
Green  Vitriol,  174. 
Gums  and  Varnishes,  293. 

Candies,  290. 
Gunmetal,  180. 
Gunpowder,  87,  128. 
Gypsum,  91,  155. 


H 


Haber  &  Le  Rossignol  Process,  81, 
H  Acid,  329. 
Hair  Tonic,  328. 
Hall,  Charles  M.,  141. 

Process,  142. 
Halogens,  88. 

Oxides  of,  89. 

Hammond,  John  Hays,  Jr.,  108. 
Hamor,  William  A.,  3. 
Hardening  Oils,  277. 
Heart  of  the  Thing,  The,  16. 
Heat,  44. 

Helium,  19,  44,  350. 
Hematite,  174. 
Heroult,  141. 


367 


EVERYMAN'S    CHEMISTRY 


Hewitt,  Peter  Cooper,  76. 
Holmium,  350. 
Hooker,  Albert  H.,  94. 
Humidity,  69. 
Hydrates,  70. 
Hydrazine,  86. 
Hydrazobenzene,  335. 
Hydrazoic  Acid,  86. 
Hydrochloric  Acid,  47,  89,  91, 
Hydrofluoric  Acid,  89. 
Hydrogen,  67,  350. 

Peroxide,  69. 

Sulphide,  97. 

Hydrogenation  of  Oils,  272. 
Hypo,  107. 

Hypochlorous  Acid,  92. 
Hyposulphite  of  Soda.  107. 


Ice  Stone  of  Greenland,  118. 

Why  it  Floats,  69. 
Indigo,  338. 
Indium,  350. 
Inorganic  Chemistry,  57. 
Inventors,   13. 
Iodine,  24,  88,  89,  94,  350. 
lodoform,  267. 
Ion,  Meaning  of,  29. 
Ionic  Hypothesis,  26. 
Ions,  45. 

Iridium,  213,  350. 
Iron,  163,  350. 

and  Steel,  163. 

Blast  Furnaces,  164,  165. 

Carbide,  167,  168. 

Carbonate,  163. 

Cast,  168. 

Chromite,  197. 

in  Water,  75. 

Metallurgy  of,  164. 

Ore,  Supplies  of,  175. 

Ores,  163,  174. 

Oxides,  163,  174. 

Pyrites,  97,  164. 

Rust,  174. 

Salts,  174. 

Sulphide,  97. 

Wrought,  1 68. 
Isobutane,  235. 
Isomerism,  236. 
Isoprene,  248. 


Johnston,  Joseph  E.,  166. 
Journal  of  Industrial  and  Engineer- 
ing Chemistry,  7. 


Kalium,  122. 
Kalkstickstoff,  154. 
Kaolin,  142,  144. 
Kekule",  Professor,  285. 
Kelp,  Giant,  124. 
Kerosene,  239. 
Ketones,  266. 
Ketoses,  283. 
Kieselgahr,  134. 
Kobolds,  196,  197. 
Kohman,  Dr.,  300. 
Kraft  Paper,  308. 
Krypton,  44,  350. 


Lampblack,  224. 
Langmuir,  Irving,  34 
Lanthanum,  350. 
Lard,  269. 

Oil,  271. 

Laundering,  279. 
Lead,  187,  350. 

Acetate,  193. 

Bicarbonate,  193. 

Carbonate,  188,  193. 

Curious  Liquefaction  of,  188. 

Dioxide,  190. 

Glazes,  144. 

Halogen  Compounds,  189. 

Hydroxide,  193. 

Molybdenate,  202. 

Monoxide,  189. 

Nitrate,  193. 

Pencils,  222. 

Peroxide,  190,  191. 

Persulphate,  191. 

Poisoning,  189. 

Salts,  192. 

Sesquioxide,  189. 

Soft,  190. 

Suboxide,  188,  189. 

Sugar  of,  193. 

Sulphate,  191,  193. 

368 


INDEX 


Lead,  Sulphide,  188,  193. 

Tetraoxide,  189. 
Le  Blanc,  Nicholas,  120. 

Process,  120,  121. 
Lepidolite,  128. 
Levulose,  283. 
Life,  Elements  in,  41. 
Lignite,  227. 
Lime,  149. 

and  Magnesia,  148. 

Chloride  of,  152. 

in  Glass,  136. 

Kilns,  151. 

Milk  of,  151. 
Lime-soda  Process  for  Softening 

•Water,  72. 
Limestone,  148,  149. 
Limonite,  174. 
Linoleic  Acid,  273. 
Linseed  Oil,  296. 
Liquid  Fuels,  227. 
Liquids,  22,  24. 
Litharge,   189. 
Lithia  Mica,  128. 
Lithium,  128,  350. 

Hydroxide,  129. 

Salts,  129. 
Litmus  Paper,  48. 
Little,  Arthur  D.,  310. 
Lubricating  Oils,  214. 
Luminous  Paints,  155. 
Lunar  Caustic,  206. 
Lutecium,  351. 


M 

Magenta,  331. 
Magnesia,  158. 
Magnesite,  161. 
Magnesium,  158,  351. 

Carbonate,  158. 

Chloride,  160. 

Disilicate,  161. 

Hydroxide,  158. 

Metasilicate,  161. 

Nitride,  159. 

Oxide,  158. 
Magnetite,  164. 
Malconite,  176. 
Malonic  Acid,  257. 
Maltose,  284. 


Manganese,  201,  351. 

Bronze,  181. 

in  Water,  75. 

Steel,  173- 
Marble,  148. 
Margaric  Acid,  255. 
Martin,  Geoffrey,  40,  49. 
Matches,  in. 
Matter,  Nature  of,  16. 

Phases  of,  24. 
Meerschaum,  161. 
Mellon  Institute,  35,  281,  300. 
Mendele"ef,  Professor,  40. 
Mercuric  Chloride,  215. 

Oxide,  214. 
Mercurpus  Chloride,  215. 

Oxide,  214. 
Mercury,  214,  351. 

Arc-light,  76. 

Bichloride,  215. 

Fulminate  of,  215. 

Sulphide,  97,  214. 

Thiocyanate,  215. 
Metallurgical  and  Chemical  En- 
gineering, 7. 
Metaphosphoric  Acid,  116. 


Metastannic  Acid,  186. 
Methane,  235,  237. 
Methylalcohol,  258. 
Methylamine,  312. 
Methylchloride,  245. 
Methylendiamine,  335. 
Methylene  Blue,  338. 
Methylethylamine,  312. 
Metric  System,  257. 
Mica,  146. 
Milk  Sugar,  284. 
Minium,   189. 
Missouri  Clay-eaters,  41. 
Mitscherlich  Process,  308. 
Modifications,  Allotropic,  95. 
Moissan,  220. 
Moisture  in  the  Air,  69. 
Molasses,  288. 
Molecules,  17. 
Molybdenum,  202,  351. 

Steel,  202. 

Sulphide,  202. 
Monel  Metal,  197. 
Mononitrocellulose,  304. 
More  about  Air,  77. 
More  Metals,  176. 

369 


EVERYMAN'S    CHEMISTRY 


Mortar,  150. 

Magnesia  in,  150. 
Municipal  Chemistry,  94. 
Muriatic  Acid,  47,  91. 

N 

Naegeli,  Professor,  303. 

Names  and  Phrases,  Chemical,  54. 

Naphthalene,  317,  323,  327. 

Naphthylamines,  329. 

Natrium  (see  Sodium). 

Natural  Gas,  229. 

Nature's  Fixation  Process,  78. 

Nef,  Professor,  286. 

Neodymium,  351. 

Neon   44,  351. 

Nickel,  179,  196,  197,  351. 

Plating,  197. 

Steel,  173,  197. 
Nigrosine,  332. 
Niobium,  352. 
Niton,  352. 
Nitric  Acid,  49,  84,  86,  87. 

Oxide,  86,  181. 
Nitrides,  86. 
Nitrobenzol,  321. 
Nitrocellulose,  354. 
Nitro  Compounds,  312. 
Nitrogen,  44,  77,  352. 

Compounds,  312. 

Dioxide,  86. 

Fixation,  80. 

Group,  1 1 6. 

Oxides,  101. 

Peroxide,  101. 
Nitroglycerin,  87,  263. 
Nitrolime,  154. 
Nitrotoluol,  321. 
Nitrous  Oxide,  86. 
Noyadont,  Dr.,  8. 


Ocher,  174. 
Oildag,  222. 
Oil  Gas,  243. 

of  Vitriol,  105. 
Oils  and  Fats,  256. 
Oils,  Hydrogenation  of,  272. 

Refining  of,  269. 
Olefins,  45. 


Olefins  and  Acids,  247. 
Oleic  Acid,  256. 
Oleomargarine,  275. 
Oleo  Oils,  275. 
Oleum,  103. 
Olive  Oil,  271. 
Opals,  134. 

Open-Hearth  Steel,  170. 
Organic  Chemistry,  233. 

Compounds,  52. 
Osazones,  285. 
Osborn,  Henry  Fairfield,  41. 
Osmium,  213,  352. 
Ostwald,  Wilhelm,  84. 
Oxalic  Acid,  256. 
Oxidation,  61. 
Oxidizing  Agents,  93. 
Oxy-acetylene  Flame,  62,  250. 
Oxy cellulose,  305. 
Oxygen,  59,  62,  352. 
Oxy-hydrogen  Flame,  62. 
Ozone,  61. 


Palladium,  213,  352. 
Palmitic  Acid,  255. 
Paper,  306. 
Paper-making,  309. 
Paracelsus,  195. 
Paraffins,  238. 

and  Petroleum  Bodies,  235. 

List  of,  245,  246. 
Paranitraniline,  326,  336. 
Para  Red,  336. 
Paris  Green,  114. 
Peanut  Brittle,  291. 

Oil,  271. 
Pentane,  236. 
Percolator,  The,  131. 
Periodic  Law,  38. 
Permanganic  Acid,  201. 
Permutit,  72,  73. 
Peroxide  of  Hydrogen,  69. 
Petroleum,  The  Future  of,  244. 

Refining,  239. 

Pharaoh's  Serpent's  Eggs,  215. 
Phases  of  Matter,  24. 
Phenol,  327. 
Phosphate,  Acid,  105. 

Rock,  no. 
Phosphine,  109. 


370 


INDEX 


Phosphonium,  no. 
Phosphor  Bronze,  113,  181. 
Phosphoric  Acid,  116. 
Phosphorus,  109,  352. 

and  Metals,  112. 

Arsenic,  Antimony  and  Bis- 
muth, 109. 

as  Brain  Food,  113. 

in  Iron,  112. 

Pentoxide,  110. 

Sesquisulphide,  112. 
Phossy  jaw,  in. 
Photochemistry,  208. 
Photographic  Prints,  199,  207. 
Photography,  207. 
Pickling  Steel,  92. 
Picric  Acid,  322,  334. 
Pig-iron,  165,  167. 
Pipe  Clay,  144. 
Plaster  of  Paris,  155. 
Plate  Glass,  139. 
Platinized  Asbestos,  213. 
Platinum,  213,  352. 

Black,  213. 

Sponge,  213. 

Tetrachloride,  213. 
Plumbates,  193. 
Plumbic  Acid,  193. 
Pons  Asinorum  of  Chemistry,  42. 
Porcelain,  143. 
Porphyry,  134. 
Portland  Cement,  155,  157. 
Potash,  67. 

Caustic,  123. 

in  the  Soil,  125. 

Salts,  123. 

Supply,  123,  124,  125,  167. 
Potassium,  122,  352. 

Antimony  1  Tartrate,  116. 

Bromide,  127. 

Chlorate,  89,  92. 

Chloride,   127. 

Compounds,  127. 

Cyanide,  128. 

Dichromate,  199. 

Fluoride,  128. 

Hydroxide,  123. 

Hypochlorite,  92. 

Iodide,  128. 

Nitrate,  123. 

Permanganate,  201. 

Silicate,  128,  134. 


Potassium,  Sulphate,  127. 
Pottery,  143. 
Praseodymium,  353. 
Producer  Gas,  228. 
Propane,  237. 
Propionic  Acid,  254. 
Proteins,  313. 
Protoplasm,  208. 
Pyridine,  261. 


Q 


Quartz,  134. 

Glass,  135. 
Quicklime,  149. 


Radicals,  45. 
Radium,  19,  45,  215,  352. 
Raffinose,  284. 
Rain,  69. 

Cause  of,  69. 
Ramsay,  Sir  William,  44. 
Red  Lead,  189. 
Reducing  Agents,  62. 
Reduction,  62. 

Research  Corporation,  66,  167. 
Reversible  Reactions,  82. 
Rhodium,  213,  352. 
Rich  Man's  Vanity,  n. 
Rittman  Process,  243. 
Rocks,  42. 

Rollo  and  His  Uncle,  18,  26. 
Rosaniline,  330. 
Rubber,  249. 
Rubidium,  129,  353. 
Rum,  260. 
Ruthenium,  213,  353. 


Saccharides,  282. 
Sadtler,  Samuel  S.,  68,  119. 
Safety  Matches,  112. 
Salt,  90. 

Cake,  121. 

Risin'  Bread,  300. 
Saltpeter,  123. 
Salts,  Dissociation  of,  47. 

Nature  of,  45. 
Samarium,  353. 


371 


EVERYMAN'S   CHEMISTRY 


Sand,  42,  130. 

and  Clay,  130. 
Scandium,  353. 
Scheelite,  202. 
Sea  Water  in  Boilers,  160. 
Seidlitz  Powders,  117. 
Selenium,  107,  179,  353. 
Serpentine,  161. 
Sewage,  62,  79. 

Disposal  Plants,  94. 
Siemens,  Sir  Wm.,  176. 
Signal  Fires  at  Sea,  154. 
Silica,  130. 

Silicate  of  Soda,  138. 
Silicates,  134. 
Silicic  Acid,  134. 
Silicon,  130,  353. 

Bronze,  181. 

Carbide,  134. 

Chloroform,  131. 

Man,  The,  131. 
Silks,  Weighted,  187. 
Silver,  203,  353. 

and  Sulphur,  284. 

Bromide,  207. 

Chloride,  204,  206. 

Color  of,  203. 

Electrolytic  Cleaning,  205. 

Frosted,  204. 

Nitrate,  204,  206. 

Oxides,  207. 

"Oxidized,"  204. 

Sodium  Cyanide,  206. 

Subbromide,  207. 

Subchloride,  207. 
Sheffield  Plate,  204. 
Slacked  Lime,  149. 
Sleep,  Mystery  of,  60. 
Slip  Clay,  145. 
Smalt,  197. 
Smell,  Sense  of,  224. 
Smithsonian  Institution,  66. 
Soap,  71,  263,  277. 
Soapstone,  161. 
Soda,  Ammonia  Process,  121. 

Ash,  49,  119. 

Electrolytic  Process,  122. 

Water,  117. 
Sodium,  117,  354. 

Aluminium  Fluoride,  118. 

Bicarbonate,  119,  122. 

Carbonate,   118. 


Sodium,  Chloride,  90,  91. 

Cyanide,  85. 

Diuranate,  202. 

Hydroxide,  119. 

Iodide,   127. 

Metallic,  118. 

Nitrate,  117. 

Salts,  119. 

Selenite,  108. 

Silicate,  134. 

Stannate,  186,  189. 

Sulphate,  91,  117. 

Tetraborate,  147. 
Softening  Water,  Lime-soda  Proc- 
ess, 72. 
Soil,  126,  161. 

Acid,  32. 
Solids,  22,  24. 
Solid  Solutions,  30. 
Solubility  of  Azo  Colors,  3,  31. 
Solute,  30. 
Solutions,  25. 
Solvay,  Ernest,  121,  122. 

Process,  121. 
Solvent,  30. 

Some  of  the  Rarer  Metals,  203. 
Soya  Bean  Oil,  271. 
Spar  Varnish,  296. 
Spelter,  182. 
Spruce  Gum,  292. 
Stannic  Acid,  185. 

Chloride,  187. 

Hydroxide,    186. 

Oxide,  185,  1 86. 
Stannous  Chloride,  185,  187. 

Compounds,  184. 

Nitrate,  186. 

Sulphate,  188. 
Starch,  297. 

in  Grains,  298. 

Natural  Production  of,  209. 
Stearic  Acid,  255. 
Steel,  1 68. 

Stereochemistry,  236,  286. 
Stibnite,  115. 
Still  More  Metals,  195. 
Stone  Clay,  145. 
Storage  Battery,  190. 
Strontium,  354. 
Succinic  Acid,  259. 
Sugar,  Fermentation  of,  305. 

Natural  Production  of,  209. 


372 


INDEX 


Sugar  of  Lead,  193. 

Starch  and  Gums,  282. 
Sulphates,  105. 

Pulp,  308. 

Sulphide  of  Hydrogen,  97. 
Sulphides,  96,  97. 
Sulphite  Pulp,  308. 

Waste  Liquors,  318. 
Sulpho-conjugations,  105. 
Sulphonic  Acids,  318. 
Sulphur,  95,  354. 

Bichloride,  97. 

Black,  332. 

Chloride,  97. 

Colors,  333. 

Dioxide,  98,  100. 

Heptoxide,  98. 

in  Fuels,  97. 

Matches,  in. 

Sesquioxide,  98. 

Sulphuric  Acid  and  Sulphur 
Compounds,  95. 

Tetrachloride,  97. 

Trioxide,  98,  101. 
Sulphuric  Acid,  49,  98. 

Anhydrid,  103. 

Chamber  Process,  101. 

Contact  Process,  103. 

Proposed  Process,  105. 
Sulphurous  Acid,  100. 
Sun's  Rays,  Power  of,  209. 
Symbols,  356. 


Thorium,  354. 
Thulium,  355. 
Tin,  184,  355. 

Cry,  The,  184. 

Disease,  185. 

Pest,  185. 

Pyrites,  185. 

Sulphide,  185,  187. 
Tinstone,  185. 
Titanium,  355. 
T.  N.  T.f  321. 
Toluidine,  327. 
Toluol,  320. 
Tricalcium  Aluminate,  156. 

Silicate,  156. 
Tridymite,  132. 
Trimethylamine,  312. 
Trinitrocellulose,  304. 
Trinitrochlorbenzol,  334. 
Trinitrophenol,  334. 
Trinitrotoluol,  321. 
Triphylite,  128. 
Tungsten,  202,  355. 

Steel,  173. 

Trioxide,  202. 
Tungstic  Acid,  202. 
Turkey  Red,  337. 

Oil,  271. 
Tweedledum     and     Tweedledee, 

Philosophy  of,  33. 
Twitchell,  Ernest,  278. 
Tyndall  Test,  103. 
Type  Metal,  115. 


Table  Salt,  90. 
Talc,  161. 
Tallow,  269. 
Tanning,  200. 
Tannin,  322. 
Tantalum,  354. 
Tartar  Emetic,  116. 
Tellurium,  179,  354. 
Tempering  Steel,  172. 
Terbium,  354. 
Terpene,  249. 
Test  Factories,  14. 
Thallium,  354. 
Thenard's  Blue,  197. 
Thermit,  198. 
Thiosulphuric  Acid,  107. 
Thomson,  Sir  William,  32. 


U 

Ultra-violet  Rays,  76. 
United  States  Bureau  of  Mines,  5. 
Unsaturated  Acids,  255. 
Hydrocarbons,  247. 
Uranium,  202,  355. 


Valence,  43,  356. 
Vanadium,  355. 
Steel,  173. 
Van't    Hoff,    Jacobus    Henricus, 

236,  285. 
Varnishes,  293. 
Vat  Dyes,  339. 


373 


EVERYMAN'S    CHEMISTRY 

Vermilion,  214.  X 

Vinegar,  254. 

Vitriol,  Oil  of,  49.  Xenon,  44,  356. 

Y 

W  Yeast,  306. 

Food,  301. 

Washing  Clothes,  93,  279.  Yellow  Ocher,  199. 

Water,  69.  Ytterbium,  356. 

Chlorination  of,  93.  Yttrium,  356. 

Gas,  228. 

Glass,  138.  Z 

Hard  and  Soft,  70.  Zeolites,  73. 

Permanent  Hardness,  71.  Zincates,  181. 

Temporary  Hardness,  71.  Zinc,  181,  356. 

Whisky,  260.  Blende,  97,  182. 

White  Lead,  193.  Chloride,  181,  182. 

White  Vitriol,  184.  Dust,  182. 

Willson,  83.  Oxide,  181,  183  . 

Window  Glass,  138,  139.  Oxychloride,  183. 

Wine,  260.  Refining,   182. 

Wire  Glass,  139.  Silicate,  182. 

Wood  Alcohol,  258.  Sulphate,  28,  181,  184. 

Pulp,  Mechanical,  307.  Sulphide,  97,  155,  182. 

Wulfenite,  202.  White,   183. 

Wulframite,  202.  Zirconium,  356. 


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